6BR dimensions for 105 Berger hybrid

[jjbduke2004]

I have an Eliseo R5 build from 2015 that I never took out to shoot. Things happened faster than I had planned, and my smith (local Benchrest smith and competitor) chambered it in a three pass process (body reamer, neck reamer, throat reamer) according to dummy cases I had provided. It's "no turn neck" if that makes a difference.

What I was supposed to do was buy a reamer from PTG and give it to the smith. I didn't. Anyone shoot 105 Berger hybrids jumped? If you don't mind, tell me how much jump, and if you have calipers what your COAL (nose to base), and even base to ogive (if you have comparators) is.

I want to compare "known" numbers that people use to my chamber dimensions. I'll have to get out my comparators and measure off the lands again, because it's been so long, I don't even remember how it was setup.

I want to see if the chamber is safe compared to known data. Worse comes to worse, I can have it setback and rechambered, or chambered for Dasher (brass is now available).

Thanks in advance!

 

[expiper]

with a .150" FB and touching the lands my length is 2.420"....you can do the math to see how much longer or shorter your dims, are,,,Roger

 

[CaptainMal]

I find somewhere around .012" is the right jump for me.

Another thing is you pretty much have to sort the bullets by ogive and weight. To use them out of the box in BR shooting is flirting with flyers. They are just not that precisely made. For general target they are fine.

 

[jjbduke2004]

Another thing is you pretty much have to sort the bullets by ogive and weight. To use them out of the box in BR shooting is flirting with flyers. They are just not that precisely made. For general target they are fine.

It's not for BR, it's for NRA prone (it's notionally an XTC rifle, but I don't plan on shooting much XTC).

with a .150" FB and touching the lands my length is 2.420"....you can do the math to see how much longer or shorter your dims, are,,,Roger

Thanks for getting back to me with your numbers. What's your usual powder load?

 

[Delfuego]

5/1000 jump for me with hybrids.
2.400" COAL
1.712" w/Sinclair gauge insert

 

[CaptainMal]

No "usual" load, especially since I do not shoot standard br cases but firearm them to both BRA and Dasher. Each barrel will tell you what it likes if you do the testing.

 

[rckendall]

My 6BR with 105 Hybrids does best at .025 jump. COAL is 2.375, reamer had a .104 freebore. While this shoots very well, I think it is about the minimum length that they should be. The rule of thumb as I know it is: 30 gn of Varget with CCI Mag Primers. Mine does well with those numbers.

Richard

 

[Rtheurer]

I have an Eliseo R5 build from 2015 that I never took out to shoot. Things happened faster than I had planned, and my smith (local Benchrest smith and competitor) chambered it in a three pass process (body reamer, neck reamer, throat reamer) according to dummy cases I had provided. It's "no turn neck" if that makes a difference.

What I was supposed to do was buy a reamer from PTG and give it to the smith. I didn't. Anyone shoot 105 Berger hybrids jumped? If you don't mind, tell me how much jump, and if you have calipers what your COAL (nose to base), and even base to ogive (if you have comparators) is.

I want to compare "known" numbers that people use to my chamber dimensions. I'll have to get out my comparators and measure off the lands again, because it's been so long, I don't even remember how it was setup.

I want to see if the chamber is safe compared to known data. Worse comes to worse, I can have it setback and rechambered, or chambered for Dasher (brass is now available).

Thanks in advance!

JJ
When I Had my Reamer made I talked with Dave Kiff on what I wanted to do. A no turn Neck. Set up for NRA prone to shoot 105gr class bullets. Just like you have done and are doing. He asked me a few questions on what bullet ( pre 105gr Hybrid) and since it was new to me I wasn't sure except I did know I was not going to try the 115's.
So He suggested, like the Gentlman above a .104 Free bore as it will handle the 107gr SMK, and the other end of spectrum the 105gr VLD Berger. One with a Short bearing serface and one with a Longer Bearing surface that puts the Boat tail further into the case.
I ended up using 105VLD's pushed into the lands soft seated. and later the 105 Hybrids. If I had known I was going to shoot those two bullets I might have gone with a .090 or there abouts.
I have used that reamer for an R5 XTC with success as well beside my Mid range prone gun.

I see what your asking to compare results so that you know if you can use the most common Powder charges that are posted with the unknown freebore that you have. I believe if you use your Hornady OAL tool and the Boat tail/Bearing surface junction is just above the Shoulder Neck junction in YOUR chamber you will be good to go. Even if its a little below.. Your still gong to be OK or just run a simple Throating reamer in and set it to what your looking for. If its to long.. shoot the 107gr Sierra Match Kings...
Dang 6BR is so resilient it will shoot anything you put in it. For NRA prone it does not need to shoot 1" groups at 600yds. But it might anyway.
Hope to see you on the line with it some day.

 

[jjbduke2004]

JJ
When I Had my Reamer made I talked with Dave Kiff on what I wanted to do. A no turn Neck. Set up for NRA prone to shoot 105gr class bullets. Just like you have done and are doing. He asked me a few questions on what bullet ( pre 105gr Hybrid) and since it was new to me I wasn't sure except I did know I was not going to try the 115's.
So He suggested, like the Gentlman above a .104 Free bore as it will handle the 107gr SMK, and the other end of spectrum the 105gr VLD Berger. One with a Short bearing serface and one with a Longer Bearing surface that puts the Boat tail further into the case.
I ended up using 105VLD's pushed into the lands soft seated. and later the 105 Hybrids. If I had known I was going to shoot those two bullets I might have gone with a .090 or there abouts.
I have used that reamer for an R5 XTC with success as well beside my Mid range prone gun.

Just as I was asking nationalmatch.us what to do (response: go to Grizzly.com, buy this SKU for a PTG reamer), my number came up in the gunsmith's backlog queue. I didn't really get a good response of what length to set my dummy cartridges to (gunsmith said he'd use them as a guide). So I made some up, but don't really remember what I did or made them too long/short.

I'll marker-up a bullet or bust out the carbide smoker and try to re-measure to the lands, then check OAL vs desired jump and see where I'm at.

I'd like to get back on the range. As of now, I'm only getting out once a year for CMP Eastern Games (Garand and Springfield). My NRA classifications just lapsed since my last approved matches were in 2015.

 

[Delfuego]

I keep hearing people recommending JGS reamers for QC and delivery reasons. I borrowed a buddies reamer for my new one. It's no-turn and think it's 105 freebore. Shoots 105 berger and 107smk well.