Cartridge (with bullet) getting stuck in chamber

[TreGrizz]

Hello, Im going to try to make this brief. I dont know if thats going to be possible... sorry.

I build / repair medical lasers for a living, I am very mechanically inclined, and have built an AR15 from the ground up, so give me the benefit of the doubt here that I know what I'm doing a little bit. I purchased a Criterion remage barrel from Northland Shooters Supply, and am having issues.

I put the barrel on the action, and then verify with a go/no go gauge (close on go, wont close on no go). I load a factory Federal berger cartridge, cycles no issue (just putting to battery then cycling bolt to remove, not firing). I load a factory barnes ttsx cartridge, cycles no issue. I load a factory nosler cartridge, and the cartridge gets stuck. I can put rearward pressure on the bolt, and with enough force it will come out, but its a crazy amount of force that requires me to regrip the bolt and barrel. This occurs with all nosler factory cartridges, and is fine with all federal and barnes factory loads. I check with an OAL gauge and see that my barrel seats a bullet 2.9" to the lands with the exact same spec nosler accubond bullet (I reload as well). I take a full length sized peice of once fired brass, and load a accubond bullet to 2.89" (0.010 off the lands). bullet goes into batter, and cycles just fine. Therefore the bullet is NOT getting stuck in the lands, its a brass issue.

Again, this is an issue with only the nosler factory cartridge. This problem doesnt exist with factory barnes, federal, or a full sized once fired case.

Heres the troubleshooting I have done. I colored the full piece of brass with sharpie, loaded and unloaded, I saw what appeared to be a gouge near where the chamber opening would be. I check with a flashlight and see a small scratch near the opening. I take some 500 grit sandpaper, and very carefull, 2 strokes max with no pressure, remove the burr. The scratches in the brass no longer occur, but it doesnt change it getting stuck. I am not comfortable on a brand new barrel sanding anything that I cannot visually see.

I have contacted NSS, and was told they have never seen an issue with a barrel being reamed bad or having and issue as I describe. Im sure it was just perspective, but I feel like it was implied that I was doing something wrong. They forwarded my information to Criterion, and I was told they would contact me. NSS would not provide me the email or phone number of the Criterion guy. Its been 4 days and I havent heard anything. Im having trouble being patient at this point...

Any insight? sorry if this is the wrong forum, I did not see a smithing or any other applicable forum.

 

[hodgeman]

Measure the unfired brass and compare the Nosler to the Federal and Remington. It could be an out of spec cartridge or your might have a chamber on the minimum side of the spec.

 

[TreGrizz]

Measure the unfired brass and compare the Nosler to the Federal and Remington. It could be an out of spec cartridge or your might have a chamber on the minimum side of the spec.

the Nosler average of 3 rounds was 0.4665 +-.0005, and the federal and barnes were both .04645 +- 0.0010. My documentation shows Saami max spec for diameter is 0.473, so all rounds are well under. I was verbally told it was a match chamber, so it is tighter I believe. As long as it shoots my reloads, and the brass doesnt get stuck, I dont care if it shoots factory nosler. I just really dont want a lemon...

 

[menhaden_man]

I was having the same problem with my 300 BLK with hand loads that weren’t crimped (coated bullets to boot). Didn’t take much addition width or a shaving of poly to dick things up.

Doesn’t sound like your problem though, but agree with checking the case specs as a starting point. Don’t blame you for wanting some customer service. It’s embarrassing too.

 

[tdot]

the Nosler average of 3 rounds was 0.4665 +-.0005, and the federal and barnes were both .04645 +- 0.0010. My documentation shows Saami max spec for diameter is 0.473, so all rounds are well under. I was verbally told it was a match chamber, so it is tighter I believe. As long as it shoots my reloads, and the brass doesnt get stuck, I dont care if it shoots factory nosler. I just really dont want a lemon...

If you have a match chamber, it wont likely be to SAAMI max specs. What are the min specs for that chamber? That's more likely to be closer to your chamber. I'd also suggest measuring the neck od and comparing it to spec.

I'm assuming you havent fired the rifle. Once you do, there'll be lots more data on your chamber size.

 

[Wapiti1]

It's not a lemon, its just a tight chamber.

SAAMI drawings list the max dimensions for the chamber and in the upper right hand corner, there should be a tolerance for those listed. It is usually Tol -0.008". So a minimum spec chamber is 0.008" smaller than the max dimension listed. Most aftermarket reamers are at or close (+0.002") to the min spec, or under if it is a custom reamer. Match is a nice word that means nothing in a custom barrel.

Brass is made to whatever spec they want. Typically, that is around 0.010-0.015" under max chamber spec, or a little more. Better brass is closer to min chamber size, IME. European brass can be off compared to US made brass for the same cartridge if they work to CIP spec verse SAAMI. It's all safe to use, just know it all has its own quirks.

Just shoot what fits, and move on. Or have a gunsmith polish the chamber with 320 grit paper.

Jeremy

 

[Ctitus25]

I've had this problem with custom bolt rifles with match barrels. Mine loves Hornady brass, but the HSM brass gets stuck. I too was told its because of how tight the chamber is. Find the brass your gun likes and roll with it.

 

[WCB]

I love the term "match chamber"....next time they say that ask for the actually dimensions. There very well could be nothing actually wrong with either the firearm or the ammunition from a industry specification standpoint. I agree with above....find something that works and stick with it., unless you absolutely have to shoot Nosler for some reason.