New KREIGER 8 TWIST , 120 freebore, 105 hybrid .007 into lands, 1st fireing after fire form,went up from 31.7--32--32.3--32.6--32.9 with RL15 never any signs of pressure... Ran test again... 32.7--33--33.2--33.4--33.6--33.8 again RL15 no signs of pressure, nothing, test today 55 degrees...guess I will run another test with Varget and see what happens...thought for sure I would run into some pressure signs! Any ideas my last barrel if I got to 32.8 you would know it ???
6BRX no sign of pressure
- Thread starter sdneil
- Start date
tclaunch
Silver $$ Contributor
Check your scale calibration.
Well the most important question should be how’s the accuracy?
I'm surprised you aren't seeing some signs of pressure with bullet jammed starting around 33.2 and up. Are you sure your powder measure is correct?
Be careful with the RL15 when the temp gets above 80....
33.6 of Varget is the absolute max for my BRX with a Brux 8 twist, 32" 105 Hybrid
Last edited:
Scale seems to be good to go...checked several bullet weights,all were on the money....dont have a chrony, so no speed data...going to try Varget tomorrow and see what happens...shot 46 rounds thru barrel now including 12 with 33.7 gr of Varget at 600 that I was happy with yesterday....accuracy with the RL 15 was poor yesterday at 300 yds...this was not the case with my last barrel...I will get it figured out!!!
Which BRX chamber do you have? Mine is the longer Chrone chamber (1.191") base to shoulder junction. I have run Moly'd 105 Bergers and 107 Sierra's with 33.5 gr. Of Varget, 33.6 of Rel 15, and 33.5 gr. of N140 without harming brass/primer pockets. All these loads run about 3015-3025 fps with good accuracy from 1-8" twist Bartlein 5R at 31". Best accuracy has been with N140. Jumping both bullets .010". Velocity from Oehler 35 with 4 ft. Screens.
nfa1...JGS reamer print says 1.1717 ( LETTER Q ) if I am reading it right... ran test today... ran up to 34.1 with Varget...no sticky bolt...no flatened primers ... no marks on case head...no nothing.. ..did shoot 12 rounds at 600...32.7 gr varget..105 hybrid...about .007 in... not to bad... 64 rounds total now
That is definitely the shorter reamer, but your freebore is .120", where mine is .104". The extra boiler room helps keep pressures lower I think. When I ran the speed up to the 3,075 fps range, I got no noticeable pressure signs at the primer, but the pockets loosened after about 4 firings. I went back to just over 3,000 fps and found a nice node that is accurate and easy on brass. My wind reading skill is not good enough to justify running it at the upper node. 3,000 or 3,100, I`'ll still shoot that 9. Might mic.the case heads and see what kind of expansion your getting there. Sounds like you`ve got a good shooter there. The BRX is a solid performer, enjoy!
Grimstod
Machinist, Designer, and Shooter.
Correct me if I am wrong but RL15 is slower then Varget. You probably will not see any pressure with it. For example I ran a test with H4350 with charges clear up to 37gr! and no pressure at all. It was actually still a mild load. Accuracy was good too but the powder was ever so slightly compressed in my BRX with .120 of freebore.
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.
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.