Gunsmithing 6mm .236 bore vs..237

[Ranger188]

I got a Rock Creek 6mm 7.5 tw in .236 bore for a great price.
I've only run .237's and never had a problem
I've read about everything I could and their is really no good or bad about a .236 bore in a 6
Does anyone have some real world experience either way?
I've heard Lapua bullets work better, boattails work better than flatbase and all copper too.
blah, blah, blah. Need some help on what to do with this blank.
Leaning towards another 6br, but what bullets would work the best?
Or just do it and shoot it, cause it doesn't matter that much.

 

[Supersubes]

Shoot it. The bore size won’t make a bit of difference.

 

[4darkseid]

I have one of each in my two Dashers both 8 twist barrels. Generally speaking it's Tomato, Tomata. I have some bullets with really fat pressure rings, I shoot them out of the .237 bore and the real skinny ones from the .236 bore. But any bullets that fall within the average range on the pressure ring, IE .2432 to .2436, shoot equally well out of either barrel. Personally I don't think you can go wrong either way.

 

[702lineman]

I've had both and cant tell a difference.

Supposedly from info I found on other sites, some 6mm bullets have a different diameter depending on the thickness of the jacket.

Think .2437" vs .2430". Idk if there is any truth to that. Supposedly jlk has smaller diameter, berger hybrids are bigger, idk. They both shoot great for me

 

[ShtrRdy]

I was wondering about this when I bought a 6mm barrel last year. What is a pressure ring that you guys are talking about?

 

[spife7980]

What is a pressure ring that you guys are talking about?

The pressure ring is where a bit of the bearing surface is actually a hair wider than the rest of the bearing surface. Not all bearing surfaces/bullet body cylinders are perfectly even. Basically the widest part of the bullet.

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[RCbadger]

I've had both and cant tell a difference.

Supposedly from info I found on other sites, some 6mm bullets have a different diameter depending on the thickness of the jacket.

Think .2437" vs .2430". Idk if there is any truth to that. Supposedly jlk has smaller diameter, berger hybrids are bigger, idk. They both shoot great for me

So here is my dilemma. Im shooting a factory barrel, 6mm creedmoor RPR. Federal Gold berger 105's, shoot great. For some reason there is a shortage so I ordered some from Copper Creek. First two rounds the primers blow out. They are seated a little further out than Federal so Im thinking they are seated too deep into the lands which may cause pressure issues. Copper Creek stated they recommend .237 not .236 bore which is a more common issue. So im stuck scratching my head. A berger is a berger. If its shooting good out of the Federal round but not the Copper Creek it cant be the bore right.

 

[702lineman]

Hard to say but sounds like load is too hot

 

[Ranger188]

Out of most of the preloaded rounds that Josh puts out, the 6 creed w/105 Berger hybrids are hot ( 3150 fps )
I would call or e-mail him. You will either get him on the phone or get an e-mail back the same day
and ask, what can be done, if you have any left. He can load them anyway you want, less powder
or any length. Really good to work with.

 

[ShtrRdy]

Copper Creek stated they recommend .237 not .236 bore which is a more common issue. So im stuck scratching my head. A berger is a berger. If its shooting good out of the Federal round but not the Copper Creek it cant be the bore right.

For the Berger 105 hr Hybrid I don't think a .236 vs .237 bore would cause a pressure problem. Like you pointed out the Federal Gold Metal works fine.