Written by Nicholas Leghorn, Benjamin Parmalee, Nathan Barndt, Frank E., Craig Boyd, Nicholas Rose. All authors are members of AwfulShootingSquad.com
Abstract
The authors of this paper conducted a 500 round stress test to determine if either of two semi-automatic shotguns, an FNH SLP Mk. I or a Mossberg 930 SPX, would experience mechanical difficulties to determine which was better suited for 3-gun competitions. Testing was conducted using one lightly used shotgun (<200 rounds) of each model. Both guns fired 500 rounds in under four hours, using two different ammunition types commonly found in stores, rotating through 6 shooters to ensure operator error was controlled for. [Conclusion redacted for the sake of dramatic tension.]
Overview
In the world of 3-gun competitions the shotgun provides a unique challenge for the competitors. Shotgun targets are typically rigged to move or react in some manner, whether it’s spinning such as with the Texas Star or flying like a clay pigeon. Typically, the competitor must fire multiple shots in quick succession to effectively neutralize the target. To decrease the time they need to take between shots, competitors (especially those in the Tactical divisions) have moved from pump action shotguns to semi-automatic models.
While semi-automatic shotguns provide a tangible benefit in terms of decreased cycling time (the time it takes to remove the spent cartridge from the gun and load a new cartridge into the chamber), the mechanisms which enable that semi-automatic operation are susceptible to failure. It is more likely that a semi-automatic shotgun will malfunction in the middle of a stage than a pump action shotgun, costing the competitor precious seconds clearing that jam. According to conventional wisdom, the number of rounds fired and the abuse the firearm has received since its last cleaning is the principal factor which increases the probability of malfunctions in semi-automatic firearms.
Methodology
This test was initiated with two specific goals. First, to determine if a modern semi-automatic shotgun would be subjected to enough wear (defined as fowling and residue produced as a byproduct of the firing of the firearm) during the course of a typical 3-gun competition to cause a malfunction. Second, to determine what differences, if any, were present between the 2 shotguns considered in the test.
Shotguns
In the world of 3-gun competitions the competitors are divided into various divisions based on the equipment they choose to use. This particular pair of shotguns are currently considered the best options for the “tactical” series of divisions (Tactical Optics, Tactical Irons, Heavy Metal Tactical) as well as the “Limited” (with restrictions) and “Open” divisions. Tactical division is generally the most popular division at any given event. For this reason the shotguns were tested in the proper configuration for a Tactical division shotgun.
| Model | Action | Modifications | Ammunition Capacity | Sights |
| Mossberg 930 SPX | Short stroke gas operated | None | 7+2 | Ghost Ring |
| FNH SLP Mk. 1 | Short stroke gas operated | None | 8+1 | Open |
Ammunition
We used two different brands: Remington #8 shot 1 ⅛ oz. target loads and Winchester Super X #8 shot, the cheapest available at Dick’s Sporting Goods and Wal-Mart stores respectively. To make sure both shotguns received the same amount of wear, the ammunition was divided evenly, 250 rounds of each brand being fired through each gun, alternating brands every 25 rounds with both shotguns firing the same brand at the same time.
Testing procedure
This test was intended to solve a question related to functioning of shotguns during a competition. We cleaned, lubricated and inspected them meticulously before the contest, as competitors would before a match. Both shotguns had seen light use prior to the test.
We designed this experiment to determine if any malfunctions occurred in any of the shotguns and to document when they happened. In the course of our work, we logged other performance results to further determine which shotgun best suits 3-gun competition.
The first such side experiment investigated whether or not the “smoothness” of the action degraded as the shotgun was fired. The action’s operation may affect the speed of the shooter, especially if malfunctions must be cleared or the action opened to abandon the weapon on a stage of competition. “Smoothness” was determined on a subjective basis before the test on a scale of 1-6, 1 being equivalent to a well-polished and oiled 1911 pistol’s slide, 6 being equivalent to an AK-47 that has significant rust and is hard to open. This subjective test was repeated again at the end of the course of fire.
For the test proper, both shotguns were fired simultaneously. To control for any issues that were purely user error, six participants rotated through shooting each shotgun in order. One at a time, each shooter would be presented with a target thrown by the assistant. He would fire at each target. Hits and misses were recorded by an observer, as well as any mechanical malfunctions.
We chose 500 rounds based on the average published round count for shotguns in 3-gun events. As the average number of shotgun rounds was approximately 100 (based on a sample size of 23 events) we decided that testing the shotguns to five times the average round count for a competition would adequately test the shotgun’s reliability, as well as establish the chances of a malfunction in the normal course of a competition.
Following the completion of testing a survey was taken of the participants to determine which shotgun they preferred. This survey was not disclosed beforehand and the owners of the shotguns in question were not allowed to participate.
Results
All results are presented in terms of “boxes of ammunition.” To make the results more readable, the smallest unit of measurement considered was a set of 25 rounds, which is the same as the amount of shells contained in a single box of ammunition. Shooters and ammunition types were rotated every 25 rounds as well, meaning each set of 25 rounds presented a unique combination of shooter, firearm, and ammunition type. By partitioning the data in this manner, the results may be viewed more as a collection of smaller tests rather than a single continuous test.
The first metric of the test was whether both shotguns were still functioning at the conclusion of the test. Indeed, both shotguns completed the 500 rounds successfully and continued functioning properly.
The second metric recorded and analyzed was how many clay pigeons were hit per box of ammunition. As the boxplot below shows, both shotguns were almost identical in terms of clay pigeons hit, suggesting that the varying skill levels of the shooters involved was properly controlled and the results would be more indicative of how the shotguns functioned rather than the shooter’s competence. 
A Welch two sample T-Test confirmed that the two distributions were statistically similar. The T statistic was 0.144 (which, with 37.83 degrees of freedom, indicates that any differences in means is probably a chance finding), the P-Value in this test was 0.8863, and the 95% confidence interval was closely straddling zero (-2.612411, 3.012411).
The final and most important metric was the reliability of the shotguns. As the boxplot below shows, the probability of a failure per box of 25 shells was far greater in the FNH SLP than the Mossberg 930 SPX.
As the graphic above shows, the final results of the test indicate that an FNH SLP is likely to have approximately five failures for every 25 rounds of ammunition, while the number of failures for the Mossberg 930 SPX is not statistically significant. However definitive that plot may look the bar graph below, illustrating total failures per box for each of the 20 boxes of ammunition, may indicate a reason.
For the 930 SPX, the failures are somewhat evenly spaced (box #1 is on the left, and box #20 with rounds 475-500 is on the right). The even distribution and sparsity of failures indicates that the failures are genuine mechanical failures due to wear and dirty machinery instead of user error. In addition, the failures occur for both Winchester and Remington ammunition indicating that ammunition type was not a factor.
With the FNH SLP, the last 10 boxes of ammunition tell a very different and interesting story. Because the failures alternate, with some bars having no failures and some bars having failures, it seems to indicate that the ammunition was to blame and not the shotgun as the malfunctions were exclusive to the Winchester ammunition. In addition, because the failures are present in multiple bars it would seem to indicate that the user was not a factor in increasing failures.
The first 10 boxes of ammunition, however, seem to negate that theory as the failures are persistent and almost evenly distributed. This discrepancy could possibly be explained as the SLP’s break-in period (the number of rounds required to put the proper level of polish on the operating mechanism for it to begin to function normally) as the shotgun was used extremely lightly (less than 200 rounds) prior to the testing.
The relatively subjective test regarding the degradation of the action due to wear proved inconclusive, as both shotguns experienced a drop in “smoothness” from a 1 to an average of 2.5. The other subjective and qualitative test, the survey, showed a marked preference for the Mossberg 930 SPX with 100 percent of the respondents preferring it in terms of its sights, weight, balance, and perceived recoil. In terms of ease of operation, however, only 67% preferred the 930 SPX to the FNH SLP.
Conclusion
Because of its consistent reliability regardless of the ammunition and the equivalent accuracy between the shotguns it is the determination of this study that the Mossberg 930 SPX is the superior 3-gun shotgun.
Special Thanks and Acknowledgements
- Thanks to the Pennsylvania Game Commission for the use of its Scotia shotgun range as the testing facility (State Game Lands No. 176).
- Thanks to The Pennsylvania State University Media and Technology Support Services for the electronic equipment used.
- Results were compiled and the survey was conducted using Google Docs (docs.google.com).
- Data analysis and figure generation was performed using the statistical program R (r-project.org).
[EDITOR’S NOTE: To clarify, the “light” piston was indeed used in the SLP Mk. I despite not being mentioned in the write-up.]
Grammar Nazi alert!
“Irregardless” is not a word.
Interesting results. I would have liked to see a Saiga and an M4 in the mix too.
Text amended.
https://www.merriam-webster.com/dictionary/irregardless
“The most frequently repeated remark about it is that “there is no such word.” There is such a word, however.”
Re: joshua on 12 Sept 2017 at 0713
The link also classifies it as non-standard, points to regardless, and after your cherry-picked quote goes on to say “Its reputation has not risen over the years, and it is still a long way from general acceptance. Use regardless instead.”
Yay! My gun wins!
Informative test, sound methodology. If only gun magazines did tests this thoroughly…
I am curious if the number of malfunctions will drop as these guns get broken in. The number and frequency seemed incredibly high compared to what I’ve seen with older semi shotguns.
One minor thing…
…defined as fowling…
Is that when a chicken gets jammed in the action?
As a wise man once said, “It’s a damn poor mind that can only think of one way to spell a word.”
On a more serious note, I would LOVE to repeat this test again in the future, throwing in a Saiga 12 and an M4 as well as the new Kel-Tec double tube shotgun when it comes out. The major constraints we had during this test was time and ammunition, we had only one day to conduct the test and a very short budget with which to conduct it. However, with some help from TTAG I’m sure we can work out a revenge match.
Great work on the test!
Surprising to see that the FN, which is supposed to be a military grade weapon, do so poorly. It is possible that it will improve once “broken in” however, I am not a fan of breaking in guns as defensive firearms should work properly right out of the box.
Rabbi:
The results of this test are so very surprising because the test itself was invalid. See my remarks in my post. My FN SLP Mk 1 has been perfect from the start. It never required any sort of break in period.
http://i154.photobucket.com/albums/s272/lanceJOregon/guns/SHOT1.jpg
Perhaps another test point would be to have a gunsmith examine the internal components for wear and fatigue after the test. A gun may perform great, yet show unfavorable wear which would limit its long-term reliability.
Man alive, this test is way so very bogus and its conclusions are totally invalid! The standard gas cylinder that comes installed in the FN SLP Mk 1 is NOT DESIGNED TO SHOOT LIGHT TARGET LOADS like those that were used in this test! The user manual for the shotgun makes this very clear.
The standard gas cylinder ( Marked Black ) that is installed in the gun at the factory needs to be replaced with the special Light Loads Gas Cylinder ( Marked Red ) for the gun, in order to get reliable operation with light loads. This article makes absolutely no mention at all of this having been done. Nor even do they mention the basic fact that there are two different gas cylinders for the FN, and that they must be swapped out depending on whether one is shooting light low base or heavy high base loads. In contrast, the Mossberg has no way to adjust its gas system for different ammunition.
So this whole test was very poorly implemented, without proper research being done by this staff. And that then created these invalid test results. I have shot numerous rounds of both trap and sporting clays with my FN SLP Mk 1 using very light target ammo, and it functions 100% perfectly, AS LONG AS I HAVE THE LIGHT LOADS CYLINDER INSTALLED!
If the test had been conducted correctly, the FN SLP Mk 1 would have very easily won.
Shame on you guys for doing such a slipshod effort here, and not doing your homework.
.
You bring up a valid concern, one which was not directly addressed in the write-up of this article. The FNH SLP Mk. I does indeed come with two gas pistons and the manual does say that light loads will properly cycle with the “light” piston installed.
The night prior to the test we fully disassembled both shotguns and gave them a thorough cleaning. While they were disassembled we referred to the manuals for each shotgun to ensure that they were properly configured for the testing to come. As was indicated by the manual for the SLP Mk. I, we installed the “light” (red) gas piston and I verified that it was installed on the firing line in the morning. So, in response to your complaint, we were fully aware of the need to change the gas pistons and we did indeed ensure that the proper piston was installed. It’s true that I own the Mossberg 930 SPX in question, Ben (who helped write this report) owned the SLP Mk. I and had a significant personal interest in seeing that his shotgun won. At the end of the test we both agreed that it had been fair, and that each of us had done everything in our power to make our shotguns run reliably. If you speak to any of the other authors involved (listed on the report) they will independently verify my statement.
While your specific complaint may not be as valid as you would have liked it to be, there is in fact a flaw with this test. The flaw is that only one shotgun of each model was used, which means we did not have a proper sample size on which to base the analysis. With production shotguns where thousands of units are produced, a sample population of dozens or even hundreds of shotguns would be required to get within a 95% confidence interval for the results. However, we did not have the time, the money or the shotguns to use a sample that large.
Despite the limitations, the results still speak volumes. A randomly chosen FNH SLP Mk. I malfunctioned more often than a randomly chosen Mossberg 930 SPX.
I apologize that your shotgun did not win. When I posted this same result at ar15.com your reaction was the same as many there: disbelief and the desire to defend your chosen shotgun. Unfortunately as far as I can tell my test was the first of its kind to actually examine the reliability of these shotguns, so the only method we have to validate the results is word of mouth. Since the testing ended there have been almost as many people who have contacted me to tell me about the poor reliability of their SLP Mk. I as have defended it. In the end, it appears that the reliability of the shotgun in question is highly variable.
That high variability brings up another question. Every 930 SPX I’ve fired and every 930 SPX owner I’ve talked to has said that their shotgun works all the time every time. However, there have been multiple SLP Mk. I owners who have returned their shotguns due to reliability issues. The variability in the reliability of the shotguns may be indicative of a quality control issue on FNH USA’s part, but further testing will be required to make any kind of a definitive answer.
I hope I have adequately addressed your concern. A great amount of time, effort and personal funds went into making this test as fair and accurate as possible, and I have not received a single penny in payment as a result from anyone. While I truthfully love comments, concerns and possible issues with my studies to be brought to my attention, I would appreciate it if future responses could be kept to a more civilized tone, and an opportunity for response be allowed before the comments devolve into accusations of “slipshod effort.”
“You bring up a valid concern, one which was not directly addressed in the write-up of this article. The FNH SLP Mk. I does indeed come with two gas pistons and the manual does say that light loads will properly cycle with the “light” piston installed.
The night prior to the test we fully disassembled both shotguns and gave them a thorough cleaning. While they were disassembled we referred to the manuals for each shotgun to ensure that they were properly configured for the testing to come. As was indicated by the manual for the SLP Mk. I, we installed the “light” (red) gas piston and I verified that it was installed on the firing line in the morning. So, in response to your complaint, we were fully aware of the need to change the gas pistons and we did indeed ensure that the proper piston was installed. It’s true that I own the Mossberg 930 SPX in question, Ben (who helped write this report) owned the SLP Mk. I and had a significant personal interest in seeing that his shotgun won. At the end of the test we both agreed that it had been fair, and that each of us had done everything in our power to make our shotguns run reliably. If you speak to any of the other authors involved (listed on the report) they will independently verify my statement.” – Foghorn
Another word, you just forgot to mention that you had the correct piston after all. Reminds me of “Dog ate the homework.” story.
OK, points well taken, and I will obviously retract my earlier remarks in light of all of this additional information being provided. Instead, I will just simply say that the writing of this article itself could have been better. Your failure to mention any of this key info in the review gave the appearance of a gross oversight being made. These details should have most definitely been included in the article, and were a significant omission to make in writing the review.
Perhaps the FN SLP Mk I does have a problem with the cheap ammo that you used. I’ve never tried these specific loads myself with my SLP, as I generally shoot Federal and Estate target ammo that I get from places like Sportsman’s Warehouse, Dick’s Sporting Goods, and a local chain called BiMart that we have here in Oregon. And as I said earlier, my FN SLP Mk I runs flawless, much better than your Mossberg 930 SPX performed in this test.
Personally, I don’t shop at Walmart myself. Not for anything. They put so much pressure on their vendors to cut corners to reduce pricing, that they many times end up selling a substandard product. At least that is my own personal opinion of Walmart and their products.
Regarding your new remarks, I do have an issue with one part of your follow up. Your comments that I have quoted below are pure hearsay, with no real facts or data to back them up. Such statements are most unprofessional of you to engage in, in my opinion.
If your goal here was to provide an objective and scientific test, then why do you now engage in this bashing of the FN SLP Mk I ? I find this most perplexing for you to do at this point in time. These remarks now give the appearance of bias on your part.
The remarks that I am referring to are quoted at the very end of this post. In my opinion, it was not at all necessary for you to say any of this, in order to respond to my concerns about how your tests were conducted. I find these comments to be gratuitous in nature. Clearly your own tests showed problems with the 930 SPX. Yet, you now actually contradict yourself and claim that every 930 SPX that you are aware of “works all the time every time”. Such a statement cannot come across as being anything other than biased.
“Every 930 SPX I’ve fired and every 930 SPX owner I’ve talked to has said that their shotgun works all the time every time. However, there have been multiple SLP Mk. I owners who have returned their shotguns due to reliability issues.”
Thank you. As I said, a lot of effort went into making this test as fair as possible. And I admit the writing could have been better, this was my first attempt at a “technical paper” approach and will try to do better in the future.
As to my comments, I was not trying to “bash” the SLP, I was simply reiterating some of the comments I’ve heard from other SPX owners. Obviously a lot more testing would be required to validate their claims, hence why I said “but further testing will be required to make any kind of a definitive answer.” I do admit to being biased towards the 930 SPX (because I’m the owner), but I feel that in the testing my own bias was balanced out by the bias of the SLP owner, and the relatively unbiased assistants we used. In writing the “paper” all people involved edited the text, including the SLP owner, to try and eliminate as much bias as possible.
Firearms reliability on the civilian market hasn’t been well tested. All we have to go on to determine which shotgun is superior is personal experience and gun store scuttlebutt. Hopefully sometime in the future we can definitively answer these questions, until then this test is the best I’ve seen.
“The remarks that I am referring to are quoted at the very end of this post. In my opinion, it was not at all necessary for you to say any of this, in order to respond to my concerns about how your tests were conducted. I find these comments to be gratuitous in nature. Clearly your own tests showed problems with the 930 SPX. Yet, you now actually contradict yourself and claim that every 930 SPX that you are aware of “works all the time every time”. Such a statement cannot come across as being anything other than biased.” – Lance Jacobs
“Every 930 SPX I’ve fired and every 930 SPX owner I’ve talked to has said that their shotgun works all the time every time. However, there have been multiple SLP Mk. I owners who have returned their shotguns due to reliability issues.” – Foghorn
Brilliant, Mr. Jacobs, you beat me to it. He sounds very defensive.
I never thought I would read something by someone using R on a gun website. This is my kind of review.
I hate to break it to you foghorn. Try telling me that every customer of Mossberg is happy with their crooked and short site post. And then tell me they are happy waiting for 3 months for a new barrel. I work in a gun store and have had so many complaints about the 930 SPX and mossbergs customer service that we no longer carry them. And you know I have had complaints with every owner on reliability. That being said, I can find just as many complaints about the FN online if I want to find them. Pure and simple the FN SLP MkI is far superior in build quality and function. I dont care how your ” test” results turned out. I have seen more than one of each model in operation and the FN has Never sent a competitor off course due to malfunction. Any production gun will have problems, my friends Benelli M4 has had cycling issues too. But what can you say the Mossberg really is a get what you pay for gun. Its good enough for fun but I wouldnt bet my life on it. And no I dont own any of the three mentioned shotguns.
Where are my Beretta’s and Benelli’s in this test?
I can tell you this: Both brands have models that have self-cleaning piston systems. The Benelli M2 is the choice of the Noveske 3 Gun team (Champions) and it’s never failed me. The Beretta Xplor A400 is another, albeit field type, super shot gun that’s had zero failures for me in hunting and with clays.
Finally: The SLP in the test was ‘set-up’ for failure.
How was the SLP “set-up” for failure?
Good read, some people are easly offended, all that was said ,if I read this right , is that a random Mossberg 930 run better then a random FN SPL, next time it could go the other way,so relax Francis.
Nice job on setting up the test. I understand the limitations and the amount of work involved setting up the test. Maybe sometime in the future gun companies who are interested in improving their product will perform similar tests with several hundred of their own guns, instead of waiting for an unhappy customer base to demand action.
Since my last posting I have become an owner of the SLP MKI and let me tell you through my informal testing it has fired and cycled every round I have put through it. Wall mart value pack garbage all the way to 3″ magnum rounds all on the light piston. There is no doubt in my mind now that there must have been something wrong with the FN tested.
Entirely possible. FN is giving us another to test shortly, we’ll see if that has an issue as well.
I never ment to discredit your testing, in my opinion it was very thorough. I just know that with my experiance FN builds very good firearms as does Mossberg. But in all honesty the Mossberg feels and is alot more budget minded. Good luck on the new testing and I hope your new FN performs like mine does.
Interesting test, I can only tell you that I have a FNH SLP Mark 1 and it has 2000 three gun rounds through it without so much as a hiccup. I have a Mossberg, and other brands of shotgun but only shoot my FNH. Its a very well made shotgun and never lets me down.
Nick leghorn- So whats the good word on your new FN to test? Let me just say one thing, I know I own a FN but unless you have big money or are military they will not listen to you. Love the guns – terrible service. Also one last bit, When you get it please properly clean it before you use it (or at least say you did) to keep the last of the cry babies of your back ;). I got mine covered in what seemed like cosmoline without the smell. Good luck and happy testing
-crash
I have a Mossberg 930SPX used in multi-gun. It has spotty reliability – sometimes fails to extract/eject, stovepipes, does not like a side saddle, been to Mossberg twice (replaced with new gun once). Sometimes it runs flawlessly just to drive me nuts. Thinking about an FN or Benelli
My SPX runs flawless with buckshot or slugs but with the 18.5 open cylinder barrel patterns are way loose with most buckshot or field loads past 12 yards except with Federal flight control 00 buck and Centurion Multi Defense. These shells are easily capable of headshot groups at 25 yards and I want tight groups. My SPX shot 13 inchs left at 50 yards using foster type slugs with rear sight centered. I had to move the ghost sight adj as far right as it would go. Still shoots 1 inch consistently to the left. The gun has to go. I may trade for a generation 3 SPX or sell it. The front sight isn’t slanted as some were on SPX’s, the rail & rear sight are secure. The receiver may have been drilled off center. Mossberg admits to having a few quality control issues & sight mounting. My Saiga 12 has been totally reliable and shoots dead on.
I wanted to update my first comment to correct the remark I made about my front sight not being canted. After checking front to rear sight alignment by sighting from the front sight towards the rear sight it was very noticeable that my front sight was canted badly to the left. From the shooting position it wasn’t as noticeable. I wrote Mossberg by email about the problem and they told me to ship the barrel for warranty replacement. I will update if the barrel is or isn’t warrantied. Before shipping the barrel I asked two friends on separate occassions to look down the barrel from the front sight to rear and tell me if they noticed anything. I didn’t mention the front sight being canted. Both immediately commented the front sight was canted badly to the left.
Mossberg warrantied my barrel and replaced it with a 3rd gen barrel. The barrel is thicker and has the new sight. Turn around time was less than 3 weeks. Now that the sight issue has been resolved I am very pleased with the shotgun. I haven’t had any problems with the shotgun at all and I run alot of rounds mostly Federal flite control, Centurion Multi Defense and Federal or Brenneke slugs.
I never shoot low recoil ammo. both the FNH-SPL and Bennelli M4 are great shotguns. What this article says to me is the Mossberg can reliably compete with the higher priced shotguns but in all fairness to both shotguns high power loads should have been used. I would contribute some or most of the failures to the low power ammo used. Enjoyed article, thanks.
I just recently purchased an FNH 6+1 SLP shotgun and I cleaned it and made sure the low power piston was installed. The indoor gun range I go only allows 00 buckshot and rifled slugs to be fired there so I fired the following rounds:
50 rounds of Federal XM127 9 pellet 00 buckshot that fires at 1325FPS.
25 rounds of Federal LE132 9 pellet 00 buckshot that fires at 1125 FPS
5 rounds of Federal Low recoil 9 pellet 00 buckshot that fires at 1140 FPS
25 rounds of Federal XM127 9 pellet 00 buckshot that fires at 1325FPS.
I never had any jams or failures firing any of the 105 rounds. I was worried about the semi-auto shotgun cycling so I’m keeping my SLP loaded with Federal XM127 oo buckshot.
The FN blows it away. I do evetrthing from three gun to sporting clays and turkey hunting with my FN and have had zero problems. I shot well over 1000 shells from light bird to buck. I also own a 930, its a decent gun but cant compare
SLP all the way! If the Mossberg 930x is so superior, why are SLP’s the winning all the major three gun titles??? Sounds to me like someone has a an agenda promoting Mossberg. “we performed a control test study where we suspect the Winchester ammo had an issue, but didn’t retry with another batch… but resulting data won’t be skewed” Nice controlled study! I run winchester, federal and remington bird shot, 0 malfunctions thru 2000 rounds 3 cleanings occasional spray of rem oil on bolt( that is nearly Ak47 reliable). Maybe the fact that I use mil-com lube helps a lot , but never had an issue with my SLP with bird shot, 00buck or brenneke slugs. Plus the actions are two different beasts all together, Mossberg action is semi- smooth, Fn’s action is glass- like silky smooth like a Beretta M9. Smoothest action I have ever felt in a shotgun. Finally, I thought this was a stress test, half of the 930x supporter replies have a “better bang for the buck” sounding response(after factory repairs). Listen to the Fn owners defending the SLP on it’s stand out performance, which do you think is really superior?
Enjoyed the comparison – got a 930 for 3 gun had some issues with QC initially but worked through them and now have a very nice and inexpensive gun that keeps up with the high dollar guns.
This comparison is garbage. The SLP is a fantastic shotgun and probably only second to the Benelli M2 in terms of usage by professional 3-gun shooters- who btw are shooting multiple load types during stages. I put over 300- rounds through mine today with nary a hick-up and that’s without a cleaning from last weekends action pistol work– I probably only have 1000 rds thru the gun as I just picked it up a few months ago but I have yet to experience a malfunction of any sort- all on the light piston as well. The build quality alone is tangible between the two guns which is a reflection of the way FN builds guns vs Mossberg- Mossberg makes decent stuff at a solid price FN makes top quality fire arms to include the SLP…get it straight wingnuts
Get an 870, autos are for pansies.
I previously owned the Mossberg 930 SPX and liked it.It was light and FAST! It was definateley more reliable and weather resistant than my Benelli M1S90. I managed to have one pushrod in the gas system shear off and jam inside the action, but Mossberg replaced it free. My friends 930 also had a crack in the gas system. Often the 930 had shell retention issues in the mag tube. A number of the 930s were shipped with canted front sights. I prefer the FNH gun, but the 930 is good if you have a well made one.
Thanks for the interesting article, I’m currently considering the two models tested and appreciate the information you provided.
For those TL;DR folks: my FN SLP MK1 malfunctions were being caused by my poor/incorrect stance. Try checking that if you’re having malfunctions.
I recently purchased a new FN SLP MK1. It came with a single piston (orange) that according the manual is intended to be used for both light and heavy loads.
Throughout the break in time I experienced plenty of FTE (failure to eject) and FTF (failure to feed). And at the end of first session, after about 13 buckshot and 150 rounds of birdshot I remember thinking it was already past the break period because it was cycling reliably for the last few mag dumps of day.
However, in several subsequent sessions I continued to have a consistent amount of FTE and FTF malfunctions.
Yesterday I went to my first 3gun match. As of that morning I had shot about 30 buckshot and 300 birdshot (primarily Winchester, which I’ve heard some say the SLP doesn’t favor) through it to break it in. And before the match I did a full cleaning of the piston, bolt and whatnot.
During the match, I experienced a lot of FTE and FTF malfunctions. This went on for about half the day. At which point a few of the other shooters pointed out that I needed to adjust stance so that my body was behind the gun. I have a tendency to plant my feet almost one behind the other when facing target, and I don’t lean forward.
I only had one more stage with shotgun after being advised of my incorrect stance, so I’m tentatively concluding that it was stance that was causing the issues. I plan to hit the range with 100 Winchester bulk to see if the malfunctions go away with this corrected stance. I’ll try to remember to update this thread with what I find.
Three years after this was written and it’s still a very relevant and well executed article. I’m sold on Mossberg.
Some doesn’t understand how to properly calculate a t-test and what the results mean.
I bought the FN SLP Mk1 and it choked on anything and everything put down the magazine tube. I went to my local gunsmith and he refused to even look at it, telling me that he’d worked on one twice for a previous customer and then still had to send it back to FN for a replacement. I pawned the FN. I bought a Mossberg 930 SPX and it ate everything I had with zero malfunctions. Like a shotgun is supposed to do. FN can bite me, since I can make a better club out of a 2×4.
All I have to say…if you know what you’re doing ,You can fix any problems that either one of these firearms have. As to long term wear and tear……….. Clean them and they will survive .. If yours don’t . get educated .and if it still doesn’t wanna survive get a pump. And have someone clean it for you because obviously you suck at it. ……. Great test guys .