Gunsmithing 338 Barrel Bore Over Lapped?

[700338LM]

I received a 338 super match stainless barrel from a reputable barrel maker.
When I went to index the barrel using PTG bushings and range rod, I found that the .3306 bushing very loose in the bore.
At the time this was the largest diameter bushing that I had. I have done several 338s and never needed a bigger bushing.
I used the Grizzly Rod to see if it was just the ends of the barrel but it seems to be true size thru the bore depth I can measure.

When I called the barrel maker, they said that the barrel went out at .3310 and were not concerned about it.
I found this odd, since all the other 338 barrels I have chambered were well below the .3306 bushing size.
I own 338 bushings from .3292 to .3306 in 2 tenths increments.
So I ordered bushings from PTG in .3308 and .3310. which they turned around in 3 days for me. Great service.
Tried indicating the barrel again and it feels like the .3310 is still loose and it may take .3312 to indicate this barrel.

What is the bore sizes you guys are experiencing in 338 lapped barrels. Anyone come across this before?

Not sure if I should just move on and get different barrel (the barrel maker does not seem interested in taking the barrel back).
If I do try and use the barrel, will it be a problem barrel?
Any suggestions, or potential problems, advice etc. would be appreciated.
Thanks in advance for your help.

 

[Blackbrush]

Who is the maker?

 

[700338LM]

I left that out on purpose. I don't want to give them bad rap, just in case this is really ok and I just have not come across this before.

 

[Edds]

Who is the maker?

My first guess is Pac-Nor.

 

[DAVETOOLEY]

Over the years I have chambered a lot of barrels with oversize bores not grooves. Just off the top of my head I have a .3315" bushing which has been used on several barrels. As long as the groove diameter is within spec you should be fine.

 

[700338LM]

Dave, thank you for the response. Makes me feel better about using the barrel.
I will slug the barrel to get the groove diameter. Hopefully it checks out.
If I can ask. Were there any adverse effects that you know about, in shooting the oversize barrels?
I am thinking velocity loss due to lower pressure, but I do not know how much it would affects things.
I don't think accuracy would be affected.

 

[DAVETOOLEY]

No adverse effects. These barrels were on target rifles with hand loads so there was never any comparison of say factory ammo velocities. Each barrel is somewhat of a unique individual anyway. I know the barrels that are used throughout the SOF community and I'm sure there are differences in bore dimensions. No one seems concerned.

 

[Straight Shooter]

I have had barrels that a whole range rod would fall through and they still shot okay. I don't dial that way but use the range rod to help determine bushing size.

If you start slugging bores you will see barrel making still has a long ways to go before perfection.

 

[Bugholes]

Larger bore dimensions, in my opinion, have shown tendencies to being more forgiving barrels- you may occasionally find them to be a little slower as well (assuming bore and groove are both a little large). It's nothing to avoid

 

[Killswitch Engage]

I have a Schneider contract barrel I just did with bore of .3012. It shoots like a house of fire and has normal velocity for length and load.

 

[700338LM]

Thank you all for your help, and sharing your experience. Moving forward with the barrel install.