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Chamber throat friction with bullet - normal??

jrsandiego12

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Minuteman
Feb 11, 2020
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San Diego, CA
I have an Impact Precision action and barrel (Bartlien by Stuteville, sorry if spelling is off). 6.5 Creedmoor with about 1400 rounds on it.

I am trying to measure the lands - really erosion since original bullet seating depth was determined at about 200 rds. Using a Hornady OAL gauge with modified Hornady case and bullet. (I know, should use a custom fire formed case, but I accidently resized that neck, lol).

So here is the issue, when I push the bullet forward with the gauge, I can feel friction in the throat before it is hard into the lands. First that makes finding a just touching point almost impossible. But second I wonder if this isnt causing some mild bolt resistence when I run the gun.

I have cleaned the heck out of it, scoped it, and its about as clean as possible with 1400 rds of wear evident. I have used a Hornady 140 ELD-M which consistently measures .264 in diameter, and 140 Berger Hybrid Target which consistently measures .2635 in diameter. The Berger has less friction, but still some. (I can see friction rubs on the circumference of both bullets.)

Is this normal for the throat to be this tight?? Ive never noticed it before. I was under the impression that the bullet didnt touch the throat circumference?

It doesnt seem an issue when I run the gun, but want to know in the future what I should expect for the chamber throat.

THANKS FOR ANY INSIGHTS.
 
Just about any runout in the case mouth will show up as scuffs / resistance on one side of the bullet.
With a fired and slightly sized concentric case
I’m betting it doesn’t have resistance.
Personally I seat a bullet long and slowly close the bolt stopping if there is resistance and seating it slightly more until it closes and has the slightest resistance/ small marks showing the lands.
Works best without the ejector and firing pin.
 
Will let more experienced guys add to this as i do not know the true answer, I recently found the same thing with my 6.5 prc finding lands with Berger 156, Nosler 140 and Hornady 143 ELDs, they all seemed to have a slight friction before getting the lands, Rifle was new, I assumed it was normal, not having any pressure issues or heavy bolt lift. Accuracy im happy with.
 
Yes, Yes - the Wheeler method. Even with this the bullet is going to have tension touching the throat walls. It should only have tension on the bolt movement when the bullet touches the lands - well thats my understanding anyway.

Seandradamus - I was careful and the scuffs are uniform around the bullet from the throat. The bullet has almost no friction in the Hornady modified case.

I guess my key question - should the bullet be touching the throat walls?
 
Yes, Yes - the Wheeler method. Even with this the bullet is going to have tension touching the throat walls. It should only have tension on the bolt movement when the bullet touches the lands - well thats my understanding anyway.

Seandradamus - I was careful and the scuffs are uniform around the bullet from the throat. The bullet has almost no friction in the Hornady modified case.

I guess my key question - should the bullet be touching the throat walls?

With the wheeler method, you don’t feel anything at all once you back out of the lands slightly. And only very slight feel when barely touching.