• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

68 grain velocities N135

Had a new .272 no turn, zero free bore 6BR. put together with a 13.75 twist Bartlein barrel finished @25" on a M700 SS. single shot with a PT&G bolt, trued up.
I fire formed some new Lapua brass with 30.0-31.0 grains of N135 first, FLS with .266 bushing after firing. Decided to strap on the Magnetospeed to see what kind of velocities I'd be getting with some 68 grain Gentry FB bullets I picked up recently. The VihtaVouri load manual showed data for the lightest bullet being the 70 gr. Sierra, min.@29.0gr. for 2956FPS to max.33.9gr. for 3310. I figured I'd start@32.4 and go to 33.8. with them seated 10 thou. in the lands
32.4-3483fps.
32.6-3473
32.8-3543
33.0-3553
33.2-3581
33.4-3600
After the first shot I thought whoa, that's smokin, checked out the MS to see if was mounted incorrectly, looked OK so I carried on.
The last load had a bit of stiff bolt lift, not terrible, but I decided to not shoot the last 2 loads @ 33.6 and 33.8gr.
The primers looked good, not flat ,no cratering, no swipe mark from ejector. I was thinking if I can get an accurate 3200-3250 load I'd be happy, knowing that VV load data is sometimes off.
Is it just me or do these velocities sound about right? I thought they were fast myself.
Thanks
Dale
 
I shot a pair of 6BRs for several years. A 14 twist with 68gr Bergers and a 10 twist with 88 gr Bergers. Vv135 for both, won multiple matches to 500 yds. The 10 twist with the 88 Bergers was a real laser. In my. 22br with 55 gr bullets 135 has been the most accurate powder, bug holes.
 
I realize some barrels are faster than others and this one isn't seasoned yet, only has 30 rounds down it, I just thought these velocities might be off.
Think I'll run some more between 31.0-32.2 and see what that gets. I'm fairly certain there's no need to run these @3600, hard on brass and barrel I would think.
I put this rifle together to shoot "The King of the Hill"@ Rosebud outside Calgary in August, it's based off the Tack Driver shoot, with a 500 Meter (548yds.) steel stage added. I was thinking some extra velocity for that stage wouldn't be a bad thing. I'll play with it some more see where it goes.
Thanks
 
RULE NUMBER ONE.....ACCURACY TRUMPS VELOCITY...ALWAYS
Absolutely. I had a 14 twist a few years ago that I shot with the same load combo that didn't get near those velocity numbers, I was curious if that barrel was slow or this one is closer to average or fast.
I'm still fire forming brass and thought I'd check some velocities. I was a bit surprised at the numbers and difference from the VV load data and was just looking for some verification one way or the other is all.
I've got 57 rounds down it,30 more fire formed and I'll start some load development.
The Club VFS score league starts week from Wed. and the Gophers are out! Trying to squeeze some rounds down this one with next month's rain coming, hopefully.
Thanks
 
Mostly I use the crony so I can tell everyone who asks what the velocity is. I could care less, I don't tune with it. But, first thing you hear is , how fast. Easier to have an answer than explain why you don't know and don't really care.
 
t j jackson liked the 6mm br but that was before the lapua cases came around.what are your groups like at 100 and 200 yards.his were in the 1s and zeros he stated for 5 shots.barrel was a 1/14 twist and custom action.speed was around 3400 to 3500 and he used the old formed cases but had a lot of prep work.i feel with the new lapua and this can be done today.
 
Cooper M22 MTV 6BR 26" barrel. 31.5 grs. N135, 68 gr. Euber, Rem 6BR brass 3452 fps Admittedly this is one of the best groups ever but, all of the other groups have no paper showing between shots. 5 shots/100 yds.
The bullseye is a quarter inch. The sight in reflects being what was required to hit the dot at 150 yds. for the Cooper One-Shot competition.
 

Attachments

  • 6br5shots.jpg
    6br5shots.jpg
    717.1 KB · Views: 4
Had a new .272 no turn, zero free bore 6BR. put together with a 13.75 twist Bartlein barrel finished @25" on a M700 SS. single shot with a PT&G bolt, trued up.
I fire formed some new Lapua brass with 30.0-31.0 grains of N135 first, FLS with .266 bushing after firing. Decided to strap on the Magnetospeed to see what kind of velocities I'd be getting with some 68 grain Gentry FB bullets I picked up recently. The VihtaVouri load manual showed data for the lightest bullet being the 70 gr. Sierra, min.@29.0gr. for 2956FPS to max.33.9gr. for 3310. I figured I'd start@32.4 and go to 33.8. with them seated 10 thou. in the lands
32.4-3483fps.
32.6-3473
32.8-3543
33.0-3553
33.2-3581
33.4-3600
After the first shot I thought whoa, that's smokin, checked out the MS to see if was mounted incorrectly, looked OK so I carried on.
The last load had a bit of stiff bolt lift, not terrible, but I decided to not shoot the last 2 loads @ 33.6 and 33.8gr.
The primers looked good, not flat ,no cratering, no swipe mark from ejector. I was thinking if I can get an accurate 3200-3250 load I'd be happy, knowing that VV load data is sometimes off.
Is it just me or do these velocities sound about right? I thought they were fast myself.
Thanks
Dale
Almost the same exact numbers I get with a 58 GR VMax and 8208 powder. I backed of to what's now my standard load. 33.3 gr 8208 58 gr VMax 3585 fps.
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
166,247
Messages
2,214,765
Members
79,495
Latest member
panam
Back
Top