Bullet setback isn’t something I’ve thought much about. But after our man Tyler sent me the link to this video, I took a look at the rounds in my two primary carry guns, a P3AT and a CW9.
Maybe there was a slight amount of setback on the first round in my CW9. Or maybe that was just the standard deviation you’ll find in any two factory rounds. If there was a difference, it was no more than a millimeter. Then again, I rarely unload and reload my guns.
But for those of you who unload and reload regularly, do you check for setback? And if you find it, does it make sense to ‘burn’ those high pressure rounds at the range as he does?
I maually insert the first bullet instead of stripping it off the magazine, problem solved.
That’s tough on the gun’s extractor.
Seriously?
Yes. The extractors of many types of guns can be damaged by placing a round in the chamber and stoping the slide on it, which forces the extractor to jump over the rim. Most handguns are designed so that the round’s rim slides up under the extractor during feeding.
Guns with extractors that are under tension instead of spring loaded, like the 1911, ar especially susceptible to this.
It May cause no problems at all for a long time but eventually the extractor/spring will fail from such abuse.
Thanks for the video, I hadn’t heard about this before.
I do question why he would burn those rounds at the range after he says something to the effect of (I’m paraphrasing here), “Setback can be responsible for the infamous “Glock Ka-boom”/gun exploding, which is not limited to the Glock, but can occur in just about any caliber and just about any pistol…”
Why not just get rid of these rounds rather than risk the gun exploding?
If you are loading/unloading your carry gun enough times to cause setback, you need to be shooting more often. IMO, if you are carrying you need to run a box of ammo thru your carry piece at least once a month. And review your procedures to figure out why you’re having so many load/unload cycles. If it’s because you’re practicing your presentation, invest in a blue gun. If it’s from dry firing, cycle your ammo back into the box and use that box at your next range session. Or just get a revolver.
@Drew
I don’t shoot my carry ammo – I’ve shot enough rounds of the particular hollow points that I use to know that they work reliably with my gun but I’m not in the habit of shooting +$1 per round ammo through my gun.
Actually your suggestion “shoot more” would mean that I would unload and reload my carry ammo more exasperating the problem.
I don’t unload my carry gun, even when in the safe, very often. Really the only time I do is if I’m practice shooting, going on school grounds. Setback is still an issue I watch for though.
No not really, I just try to shoot them off every once in a while, hopefully before it becomes a real issue.
I do check for setback. I had a problem with it in factory Speer Gold Dots in .357Sig. I had four rounds set back relatively randomly in a 50 round box. I shot one but I read up on it and setback changes the chamber pressure and can cause it to rise to unsafe levels. I toss set back rounds in the dud bucket at the range when I’m shooting and don’t use Gold Dot anymore.
During failure/malfuction drills, double feeds will almost guarantee setback. The spring loaded slide is driving a round into the case head of an already chambered round.
I use a couple whacks of a kinetic puller, reseat to spec, crimp and use the round for later practice ammo.
Yet another +1 for a revolver.
And another +1 for you, too. We love revolvers.
@Joe Nobody:
Yes seriously. The extractor is made to slide up behind the rim of the cartridge as it is stripped of the magazine. There’s no impact on the extractor that way. When you load a cartridge into the chamber first, the extractor is slammed into the rim of the cartridge and is forced around it.
It’s not a problem if it only happens a few times, but repeated many times that operation can break the extractor.
Wow I feel stupid, I have veen shooting for a long time and didnt know that, probably because im a revolver guy
One can point to thousands of forum chatterings, but it is still up for debate on how damaging this is. Would bet someone real money that I could go to a range with 1000 rounds all being manually fed…all of them extracting with no breakage to an extractor.
Even the internal extractors in a 1911 has relief cuts to accommodate manual feeds.
It definitely isn’t good for the extractor but…it depends on how you do it. I used to tilt my XDm 9mm downward so that the extractor would catch on the rim of the case at approximately the same angle it would feed and chamber it that way instead of wrestling with putting #19 back in that magazine. Those mags are the only ones I’ve ever found that can persuade me not to load them fully every time…
Extractors are usually made out of high strength steel. Now, whether you will bend the extractor out of tune doing it by just setting the round in the chamber and letting it slam forward, that I think is a much greater possibility than breaking it. Out of tune is just about as bad as broken, anyway.
Yes, now…
http://i44.tinypic.com/28ck2uo.jpg
Yes I check, and no I don’t shoot the compressed rounds. This was a big problem with my .380, and a slight issue with my 1911. So far it hasn’t been an issue with my 9mms, but I still keep an eye out for it. I don’t worry about it to the point of calipering every round; I just eyeball them.
Videoman is 100% correct.
I chamber slowly and tap the slide to fully seat that first round. Before I hear it from the “slingshot it home crowd”; I know when my gun is in battery, there is no “hand chambered flyer” in my “test groups” and not much possibility of Kb inducing set-back in top two rounds that I rotate.
Hadn’t thought about this at all. Good info.
I carry a .357sig m&p. Because this cartridge has a smaller amount of case holding the bullet, set back is an issue. Especially since I load and unload my pistol at least twice a day. I have found that if I chamber my pistol slowly as I used to always do it pushes the bullet back in more quickly. So I just sling shot it now and every once in a while I take a round out that is starting to set back and set it aside to shoot at the next range session.
I have a few rounds laying around that are set back too far for me to feel comfortable shooting them. They are from when I was riding the slide home, I guess I’ll dispose of them somehow.
In most semiauto handgun cartridges, pressure isn’t going to be a huge issue. Even magnum cartridges can handle mild powder compression (which will probably stop the bullet from setting back further) without damage to the firearm. This is why they video subject feels it is ok to burn them in a practice session. What I would really worry about, especially in a defensive gun, would be feeding reliability. Not a problem if the setback round is already in the chamber. If it has been rotated back into the magazine, however, it could cause a misfeed at a really, really bad time.
Since the first two rounds in the mag are the ones that get alternately chambered with each unload/reload I just strip the first two rounds every so often and shoot them.
I’d give it some thought. Some time ago I came across this link.
http://forums.handloads.com/archive/forum_posts.asp?TID=22648&PN=1&TPN=1
In it, the typical 2.7grn Bullseye charge goes from 8,700psi to 16,100psi with 0.125″ additional seating depth. 1mm = 0.039inch, or about a third of that depth. Big deal. But look at the Magnum load, going from 34kpsi to 46kpsi with a 1/16th inch depth (or about that millimeter).
What’s all this talk about, ‘damaging the extractor’? Doesn’t anybody know how to load a round into a pistol, and use gravity to slip it underneath the extractor claw?
1. Remove the magazine, and clear the weapon.
2. Lock the slide back.
3. With the muzzle pointed in a safe direction, insert a round into the chamber, and gently, ‘ride the slide’ forward until it just touches the cartridge head.
4. Now, with the muzzle still pointed in a safe direction, elevate the muzzle to about 15 or 20 degrees. Slightly turn the pistol to the side so that you can look inside the ejection port.
5. Slowly withdraw the slide and let the cartridge slide down and partially out of the chamber. At a certain point you will see the cartridge head slip underneath the extractor claw.
6. Now, bring the slide gently forward; and the cartridge will load into the chamber in exactly the same way as if it had been pushed from behind by the slide’s pickup rail.
7. Keep that muzzle pointed in a safe direction, and reinsert the magazine. You’re, now, ready-to-go; and there ain’t going to be any top round bullet setback – Ever!
It works in my glock 19. Thanks
I tried this with a Ruger LCP .380 and could not get it to work. You are doing this procedure with what gun?
************************
David says:
September 27, 2012 at 09:52
What’s all this talk about, ‘damaging the extractor’? Doesn’t anybody know how to load a round into a pistol, and use gravity to slip it underneath the extractor claw?
1. Remove the magazine, and clear the weapon.
2. Lock the slide back.
3. With the muzzle pointed in a safe direction, insert a round into the chamber, and gently, ‘ride the slide’ forward until it just touches the cartridge head.
4. Now, with the muzzle still pointed in a safe direction, elevate the muzzle to about 15 or 20 degrees. Slightly turn the pistol to the side so that you can look inside the ejection port.
5. Slowly withdraw the slide and let the cartridge slide down and partially out of the chamber. At a certain point you will see the cartridge head slip underneath the extractor claw.
6. Now, bring the slide gently forward; and the cartridge will load into the chamber in exactly the same way as if it had been pushed from behind by the slide’s pickup rail.
7. Keep that muzzle pointed in a safe direction, and reinsert the magazine. You’re, now, ready-to-go; and there ain’t going to be any top round bullet setback – Ever!
Repeatedly chambering the same rounds can cause setback, which may lead to kaboom, but it can also cause primer compound separation, which WILL lead to a failure to fire. Happened to a cop at a critical moment:
http://youtu.be/5VSfSPuEC6M