6BR- Ackley Improved 40 degree

[X-Caveman]

What are you all getting for cleaning intervals on this cartridge, using H4895 and/or RL15?

I used 30.0gr of RE-15 & various 105s when fire forming. Maybe there wasn't enough pressure to burn completely, I don't know. Based on what I saw, I don't think it's going to be the powder for me. Accuracy was good (given no load work), but it sure seemed sooty. The bullet holes looked like Marilyn Manson's eyes & the barrel was very tough to get clean. In our local games, we need 50+ accurate rounds between cleanings, so I'm switching to H4895 for load work up.

 

[JamesnTN]

Got the 6 BRAI out this morning and did a ladder test using the CCI 450 and CCI400 with H 4895 and my bullets.

Initial 100 yard test favored the 450's but then at 600 that changed drastically.

These were shot at 600 yards

 

[swd]

Got the 6 BRAI out this morning and did a ladder test using the CCI 450 and CCI400 with H 4895 and my bullets.

Initial 100 yard test favored the 450's but then at 600 that changed drastically.

These were shot at 600 yards




View attachment 1013915


View attachment 1013914

How do they handle pressure compared to 450's?

 

[dbduff]

Did you change powder weight with mag primers? What variables other than primers accounts for tightening of groups?
D

 

[JamesnTN]

Did you change powder weight with mag primers? What variables other than primers accounts for tightening of groups?
D

The powder charges are listed on the targets along with avg fps and ES
On each target
#1 30.8
#2 31.0
#3 31.2

No other changes were made all loaded exactly the same to test primers and powder charge

 

[JamesnTN]

How do they handle pressure compared to 450's?

I can't answer that I've never tried to push them hard enough to pop one or get excessive pressure

 

[pat fulghum]

Just FYI... I tried Fed GM Match and would pierce the cup.... pierced 3 out of five shots ... gave up on the primers.

James, At 31.2 of H4895 with Berger 105, i'm at 2990 fps.... I am a bit faster than you.

 

[JamesnTN]

Just FYI... I tried Fed GM Match and would pierce the cup.... pierced 3 out of five shots ... gave up on the primers.

James, At 31.2 of H4895 with Berger 105, i'm at 2990 fps.... I am a bit faster than you.

I would guess I'd pick up another 15-20 fps if I shot those same loads at 85-90* instead of like this am at 67-70* but still no where close to your speeds.

 

[Pappy42]

I would guess I'd pick up another 15-20 fps if I shot those same loads at 85-90* instead of like this am at 67-70* but still no where close to your speeds.

Do you consider your barrel to be fully broken in? I've noted some velocity increases after shooting them a while. If you covered this in a previous post; I missed it.

 

[JamesnTN]

Do you consider your barrel to be fully broken in? I've noted some velocity increases after shooting them a while. If you covered this in a previous post; I missed it.

Yes this barrel has probably 300-400 rounds down it now. So it's as fast as it'll get without throwing more powder to it.

 

[johara1]

Just FYI... I tried Fed GM Match and would pierce the cup.... pierced 3 out of five shots ... gave up on the primers.

James, At 31.2 of H4895 with Berger 105, i'm at 2990 fps.... I am a bit faster than you.

I use 31.1 of H4895 and a federal 205 and never had an issue, and the same with 32.3 of RL-15 and a 205 both are with a103 or a 105 Barts bullet .... Jim

 

[kountryboy2]

I use 31.1 of H4895 and a federal 205 and never had an issue, and the same with 32.3 of RL-15 and a 205 both are with a103 or a 105 Barts bullet .... Jim

32.5 of rl-15 and a br4 gives me 2998 out of a 26" barrel. I'm going to try h4895 next 8208 shoots good for me but it's slower for me. Sorry I'm in the wrong thread I'm shooting a dasher. I'm going to try a bra next.

 

[johara1]

Tom, Maybe they will soon believe 31.105 of H4895 to be exact........ lol...... Jim

 

[Terry Altom]

Is everyone still using the 6mmBR Go gauge to headspace the 6BR-AI?

 

[johara1]

That is actually it, but I was being secretive lol.I

Tom, you drive it good so you can let them know the load ... lol. I see lack of jackets again, no bullets..... Jim

 

[johara1]

Is everyone still using the 6mmBR Go gauge to headspace the 6BR-AI?

That is what they call for at JGS. and it works so why change. it is perfect for making brass plus eliminate the work and make perfect brass. Jim

 

[Alex Wheeler]

I chamber .004 short on a 6br go gauge.

 

[Terry Altom]

Has anyone tried a Wilson 6BR or Dasher neck die with the 6 BR-AI? I like those for load development at the range. I assume the BR one would need to have its shoulder reamed.

 

[Alex Wheeler]

A dasher neck die will work with .080 cut off and br will need to be reamed to make the shoulder 40 degrees. Of course if its a wilson neck size hand die you can make a spacer that .080 that is the size of the case head and put it on the case head when you push the case into the die. Thats will push the case in deeper.

 

[Raythemanroe]

I have the (eighty thousandths short) Harrels D3, hopefully that works...


Ray