What happens if bullet is touching the rifling?

[KustomHolsters]

I am loading a valient 180gr lrnfp bullet at 1.131 oal length and the finished rounds wont drop in and out of the chamber of my kkm glock barrel, it acts like it is getting stuck in the rifling. My crimp is good which leads me to my question, what could be causeing this? Do i need to throte my barrel for the larger lead bullet diameter?

Thanks

Sorry, meant 1.131 oal

Edited January 18, 2015 by KustomHolsters

[bowenbuilt]

1.310 is probably not going to work in your magazines either. For a KKM Glock barrel try loading at 1.135 OAL and you should be just fine.

Edited January 17, 2015 by bowenbuilt

[Pat Miles]

Generally, if the bullet is parked in the rifling the pressure will spike into a potentially dangerous situation. Rifle shooters will sometimes put the bullet into the rifling looking for better accuracy but they will build a load so as not to go into an over pressure situation.

Caution is needed.

[mike cyrwus]

1.310 is probably not going to work in your magazines either. For a KKM Glock barrel try loading at 1.135 OAL and you should be just fine.

-provided you dont mis measure your powder charge either. Be careful.

[Sarge]

I guess it could be argued that barely touching would be OK. BUT with oal variations being what they are you will get longer ones in the mix and that will be an overpressure situation waiting to happen. We don't want even our longest rounds that come off the press to touch anything. And like Bowen said, with Glocks you can only load as long as the mags will allow. That's the first consideration in oal work up.

[DougM]

Are you sure you are touching the rifling? That OAL seems a little short to be hitting any rifling. Most chambers can tolerate well in excess of 1.135". Several things come to mind. Are you absolutely sure your crimp is OK? What does it measure at the case mouth? The KKM barrels may have close tolerance chambers and might not tolerate insufficient crimping. I had similar problems with a 40S&W M&P that turned out to be a crimping issue. I just turned down my taper crimp die (seating and crimping in separate steps) and the problem was solved. Next, do some rounds chamber and others not? Are any of your cartridges "glocked"?

I'd suggest you get a black marker and coat the bullet and casing, then insert it in the barrel (out of the gun, of course) and try to rotate it. Then pull it out and see where the marks are. That will tell you what is going on. Then get back to this group and someone will point you to a solution.

[KustomHolsters]

The only thing i can figure is that the lead bullets are sized to .401 which is causing them to fit it the chamber but not drop out freely. No my brass is not glocked and i am posetive that my crimp is good. Gonna try to just shoot them like they are. Thanks

[Steve RA]

Many of the aftermarket, replacement barrels come with very short chambers. I just put a Kart barrel (9mm) in and it had no "throat", just a square joint where the chamber ended and the rifling started. Sent a dummy round and the barrel to a gunsmith I know and had the barrel throated.

One way to do it is to load a dummy round so it fits in the magazines with a reasonable amount of clearance and throat the barrel to match the dummy round. Then you can probably load most bullet shapes that you may want to use.

[JimmyZip]

I am loading a valient 180gr lrnfp bullet at 1.131 oal length and the finished rounds wont drop in and out of the chamber of my kkm glock barrel, it acts like it is getting stuck in the rifling. My crimp is good which leads me to my question, what could be causeing this? Do i need to throte my barrel for the larger lead bullet diameter?

Thanks

Sorry, meant 1.131 oal

Probably

Many of the aftermarket, replacement barrels come with very short chambers. I just put a Kart barrel (9mm) in and it had no "throat", just a square joint where the chamber ended and the rifling started. Sent a dummy round and the barrel to a gunsmith I know and had the barrel throated.

One way to do it is to load a dummy round so it fits in the magazines with a reasonable amount of clearance and throat the barrel to match the dummy round. Then you can probably load most bullet shapes that you may want to use.

This would be your answer right here.

[bowenbuilt]

I totally agree. There is nothing worse than a short throated/tight barrel to aggravate the hell out of you when for $35.00 it can all be fixed forever. You will feel much better after the surgery.

[noylj]

The solution to chambering problems is always the same:

Take the barrel out of the gun. Drop rounds in until you find one that won't chamber. Take that round and "paint" the bullet and case black with Magic Marker or other marker. Drop round in barrel (or gage) and rotate it back-and-forth.
Remove and inspect the round:
1) scratches on bullet--COL is too long
2) scratches on case mouth--insufficient crimp
3) scratches just below the case mouth--too much crimp, you're crushing the case
4) scratches on case at base of bullet--bullet seated crooked due to insufficient case expansion (not case mouth flare) or improper seating stem fit
5) scratches on case just above extractor groove--case bulge not removed during sizing. May need a bulge buster.

[sdrr72]

You are not hitting the rifling.

I have two KKM barrels for my G35's, and I had your same problem with the first. Ship it back to KKM with a couple of dummy rounds that do not seat (no powder or primer), and a note asking them to ream out the barrel for 0.401 lead bullets. They will measure your samples to check, then find a reamer that is as close as possible to your sample bullets. They had mine back to me in about a week. Worked great.

I didn't have this problem with the second because I sent in dummy bullets with the order.

I promise this will fix your issue.

[johnbu]

The solution to chambering problems is always the same:

Take the barrel out of the gun. Drop rounds in until you find one that won't chamber. Take that round and "paint" the bullet and case black with Magic Marker or other marker. Drop round in barrel (or gage) and rotate it back-and-forth.

Remove and inspect the round:

1) scratches on bullet--COL is too long

2) scratches on case mouth--insufficient crimp

3) scratches just below the case mouth--too much crimp, you're crushing the case

4) scratches on case at base of bullet--bullet seated crooked due to insufficient case expansion (not case mouth flare) or improper seating stem fit

5) scratches on case just above extractor groove--case bulge not removed during sizing. May need a bulge buster.

Very well stated!