Didn't see a specific post for the 6mm BRA and I am new to the cartridge. I will most likely run Lapua BR brass, CCI 450, H4895, and haven't decided on projectile.
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6mm BRA
- Thread starter cjherrman
- Start date
I'm on 6BRA barrel #2
Fireform load on virgin Lapua brass, 29.8 Varget behind a 105gr bullet, Federal 205 primer, brass was a natural light crush fit in chamber but I jammed bullet too for good measure. All fireforming rounds shot lights out, one ragged hole.
Barrel #1 shot Varget slightly better than H4895 initially, was at 31.6gr behind a 105 Hybrid with CCI450 primer, 2950 fps 26" barrel. That got a bit sticky on bolt lift eventually so backed it down to 31.4, then after about 1400 rounds I went back to H4895 and tried a different lot of powder and ended up at 30.6gr which shot super accurate. Its slowed down a bit lately went from 2896 fps at 1800 rounds down to 2875fps at 2100 rounds. Still shooting 0.2 to 0.3MOA for 5 shot groups and holding SD of 3 or 4. I'm only using it for club matches now though.
Barrel #2 went straight to H4895, settled on 30.4gr behind a 105 Hybrid, getting 2919fps from a 27.5" barrel. Also stupid accurate at 0.2MOA 5 shot groups and super low SD's.
I've pushed it up near 3000 fps with a 105 on the first barrel, but for long term use and comp shooting I'd rather be slow/steady and trouble free.
Fireform load on virgin Lapua brass, 29.8 Varget behind a 105gr bullet, Federal 205 primer, brass was a natural light crush fit in chamber but I jammed bullet too for good measure. All fireforming rounds shot lights out, one ragged hole.
Barrel #1 shot Varget slightly better than H4895 initially, was at 31.6gr behind a 105 Hybrid with CCI450 primer, 2950 fps 26" barrel. That got a bit sticky on bolt lift eventually so backed it down to 31.4, then after about 1400 rounds I went back to H4895 and tried a different lot of powder and ended up at 30.6gr which shot super accurate. Its slowed down a bit lately went from 2896 fps at 1800 rounds down to 2875fps at 2100 rounds. Still shooting 0.2 to 0.3MOA for 5 shot groups and holding SD of 3 or 4. I'm only using it for club matches now though.
Barrel #2 went straight to H4895, settled on 30.4gr behind a 105 Hybrid, getting 2919fps from a 27.5" barrel. Also stupid accurate at 0.2MOA 5 shot groups and super low SD's.
I've pushed it up near 3000 fps with a 105 on the first barrel, but for long term use and comp shooting I'd rather be slow/steady and trouble free.
Thanks for the info. I figured with the new popularity of this cartridge I would have more responses. Let’s keep it going.
Here is my 6BRA recipe:
- Berger 105 hybrids
- Lapua brass
- CCI BR4 primers
- 30.6 grains H4895
This combination has a velocity of ~3000 fps out of a 28" Kreiger HV barrel. Shoots tiny groups with ~3-4 SD.
- Berger 105 hybrids
- Lapua brass
- CCI BR4 primers
- 30.6 grains H4895
This combination has a velocity of ~3000 fps out of a 28" Kreiger HV barrel. Shoots tiny groups with ~3-4 SD.
Hi Team, just jumping into 6 BRA...barrel should be here in the next 2-3 weeks, Nucleus receiver ready to go. Planning on starting with 105 Hybrids and SMK 107s--new Lapua brass, CCI 450s and either H4895 or Varget. Will update this post on progress....
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6 BRA FIRE FORM load:
- New Lapua 6 BR Brass
- CCI 400's
- Berger 105 Hybrid
- 30gr. Varget
- .015 off lands
I am not sure of the velocity as I am still just screwing around fire forming. This is from a 26" Impact Precision by Stuteville that was bought pre-chambered from Impact Precision Shooting and I simply threaded it onto my Impact receiver.
The attached target is just a fun little "varmint match" target that dad and I shoot at 200 yards off a bipod, rear bag and bench. We have fun with it. These are shots 64-73 down the new barrel. Penny in picture is for "bulls eye" reference.
There was no "science" to this load, just took 6BR load data. My father also shoots a straight 6BR so I was able to piggy back off of him also.
- New Lapua 6 BR Brass
- CCI 400's
- Berger 105 Hybrid
- 30gr. Varget
- .015 off lands
I am not sure of the velocity as I am still just screwing around fire forming. This is from a 26" Impact Precision by Stuteville that was bought pre-chambered from Impact Precision Shooting and I simply threaded it onto my Impact receiver.
The attached target is just a fun little "varmint match" target that dad and I shoot at 200 yards off a bipod, rear bag and bench. We have fun with it. These are shots 64-73 down the new barrel. Penny in picture is for "bulls eye" reference.
There was no "science" to this load, just took 6BR load data. My father also shoots a straight 6BR so I was able to piggy back off of him also.
Attachments
So is H4895 the magic for BRA like Varget is for Dasher? I shoot both dasher and BRA now, so would be nice to just run 1 powder. However, I'm hearing of very good results with BRA and H4895. I've been FF with varget this far. I'll probably have to try them both, but curious what others experience has been.
H4895 just as temp stable as Varget?
H4895 just as temp stable as Varget?
Both shot well for me, some guys have had good results with Varget. I ended up getting slightly better accuracy from H4895 and that is more commonly what the benchrest guys have used for their world records. Didn't test Varget in my latest barrel since H4895 shot well out of the gate.
I tested temp stability with H4895 and it was very reasonable. It was a cold day outside, about 40 degrees. I left 5 rounds outside until they fully cooled to ambient temperature. I took another 5 rounds and sat in the car with the engine running and the heater on and held the rounds in the hot air of the heater vent until they were quite warm. Probably 85-90 degrees. Warmed up the magazine too so it would stay warm when I jumped out of the car and loaded the gun.
6BRA 30.8gr H4895 Sierra 110MK CCI 450 26" barrel (as an FYI this is a slow lot of H4895 compared to others)
40 degrees = 2850 fps average
85-90 degrees = 2875 fps average
29.8 Varget, RDF 105, cci450, 2840 fps, 27 inch barrel, fireform loads. Shots 8-16. 50 thou jam, 20 thou jam.
My freebore is .104, but I'm not shooting 110's in the BRA, just 105 Hybrids. The neck is so long that you could run pretty much any bullet and still be well forward of the neck/shoulder junction on the brass.
105 hybrid
H4895 seems to be nodes at 30.5ish or 31.1 ish
Lapua brass
Br4s or wsr primers
Fireform at 29.0
H4895 seems to be nodes at 30.5ish or 31.1 ish
Lapua brass
Br4s or wsr primers
Fireform at 29.0
I shoot 31gr. H4895, lapua brass, 110 smk, and cci small rifle magnum primer in my BRA @ 2965 26" bartlein. I have shot some varget as well, but landed on H4895 for the time being. 3 Shots @ 800yds pictured below
1:7.5 26” Bartlein medium palma
Lapua brass
CCI 450 primers
105JLK
31.6 Varget
2960fps
.110” freebore
so far no speed drop, same powder lot, bullet lot, same brass with 7firings
Lapua brass
CCI 450 primers
105JLK
31.6 Varget
2960fps
.110” freebore
so far no speed drop, same powder lot, bullet lot, same brass with 7firings
How is everyone neck sizing during the fireform process? Just waiting on my brass to get started... My thoughts were to see if Redding would sell a 6 Dasher neck only sizing die and ask for some material off the bottom. Which might be trial and error to dial in. Or will any 6 bra sizing die be sufficient?
I am just loading 6br virgin brass with a light load .020 into the lands to fireform. Then full length sizing with a whidden 6 bra bushing die.
Depends on your chamber if the Whidden die will work. Ask your gunsmith for the reamer print and the die company will be able to tell you if their die is right for your chambering.
To get 3 firings I just tapped a .265" bushing on 3 of my brass to get neck tension. You don't need to size your whole neck to fire form.
I had to put them in my press without a die to pull the bushing off by hand.
Then you can send your 3x fired brass in to get the exact size die you need.
To get 3 firings I just tapped a .265" bushing on 3 of my brass to get neck tension. You don't need to size your whole neck to fire form.
I had to put them in my press without a die to pull the bushing off by hand.
Then you can send your 3x fired brass in to get the exact size die you need.
i use a BRA die from whidden with a COAX...the die would bump the shoulder .0015 but was over camming pretty good so i had my smith take .035 off the bottom and its perfect.
you can buy a dasher die and have .080 taken off the bottom and it should be good or just buy a harrels 6BRA die....OTM has them instock.
you can buy a dasher die and have .080 taken off the bottom and it should be good or just buy a harrels 6BRA die....OTM has them instock.
I tapped a bushing on the neck to get a bit of tension. It doesn’t take much to get a bullet to seat. I didn’t want to touch anything of the body to have full blown cases from shoulder to base. I did this a few times on a few pieces of brass. It’s worth the effort to have max brass life and no troubles going forward.
I'm having a second rifle with two barrels chambered as we speak.
Currently shooting a Bartlein 26" 7.5-twist 5R
- Lapua brass
- CCI BR4 primers
- Varget (30.0-gr)
- 110-gr Sierra Match King
- 2840-fps
My fire-forming load:
- FGMM 105
- RL-15 (29.0-gr)
- 105-gr Hornady BTHP
- 2700-fps (IIRC?)
No brass prep or bullet jamming for the fire-form load. Just load and shoot, no issues. Rifle chambered to give a slight crush on the neck-shoulder junction with virgin Lapua brass.
I've yet to loose a case from fire-forming. When I was shooting a Dasher, I would loose 1 out of 100 cases to a split shoulder.
I tried 4895 because all my friends shooting same cartridge says it's a more accurate load, but the difference I see is not worth chasing, plus I'm sitting on a lot of Varget.
Funny thing is, the BR4's gave me more velocity than the 450's. Makes no sense?
Currently shooting a Bartlein 26" 7.5-twist 5R
- Lapua brass
- CCI BR4 primers
- Varget (30.0-gr)
- 110-gr Sierra Match King
- 2840-fps
My fire-forming load:
- FGMM 105
- RL-15 (29.0-gr)
- 105-gr Hornady BTHP
- 2700-fps (IIRC?)
No brass prep or bullet jamming for the fire-form load. Just load and shoot, no issues. Rifle chambered to give a slight crush on the neck-shoulder junction with virgin Lapua brass.
I've yet to loose a case from fire-forming. When I was shooting a Dasher, I would loose 1 out of 100 cases to a split shoulder.
I tried 4895 because all my friends shooting same cartridge says it's a more accurate load, but the difference I see is not worth chasing, plus I'm sitting on a lot of Varget.
Funny thing is, the BR4's gave me more velocity than the 450's. Makes no sense?
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Exactly where my intentions began. How to size as many cases in the process of fireforming until that 3rd firing is complete in order to send a few to Harrell’s. All without disturbing any dimensions but the neck.
But all good things take time and it seems most, like yourself, are tapping on a bushing. Thus I’ll just be patient and go that route. I have no doubts it’ll be worth it.
Originally before I found my perfect die I only sized 10cases, I did about 3 or 4 the bushing push method. On another caliber I found that a Lee crimp die puts just enough tension to hold a bullet to continue this. I only push the die on maybe .010-.030” it’s just enough to hold a round, then I seat the bullet super long as I want it still jammed. It’s only 3-4cases I need to do this for 2-3x firings. I measured after each time to see if it was still growing. Mine was till the 3rd firing. That’s when I knew my shoulder bump, max base dimensions, max shoulder/body size. Then I was able to order the perfect die to ensure max brass life and ease of loading.
I tried them, but there was a very small window of acceptable velocities before I started getting a sticky bolt. Too bad too, as I've got 500 (well, 480 or so now) that I got when I had my 6CM. I sold it when I got my BRA, so they just sit on my shelf.
Throwing my info into the mix:
- Bartlein 26" 1-7.5
- Lapua brass
- Fire forming load is 28.6 gr H4895 with Berger 105 VLDs (I still have some from when I thought I had the patience to find their right depth)
- Regular load is 30.66 gr H4895 with Berger 105 Hybrids at .025" off, BR-4 primers. That gets me 2945 fps. This load tends to get me in the low-4 range for SDs - others get me in the 3s, but aren't as accurate.
I use a Whidden FL sizing die and just started using a Wilson seater die on an arbor press. I really like the Wilson die.
- Bartlein 26" 1-7.5
- Lapua brass
- Fire forming load is 28.6 gr H4895 with Berger 105 VLDs (I still have some from when I thought I had the patience to find their right depth)
- Regular load is 30.66 gr H4895 with Berger 105 Hybrids at .025" off, BR-4 primers. That gets me 2945 fps. This load tends to get me in the low-4 range for SDs - others get me in the 3s, but aren't as accurate.
I use a Whidden FL sizing die and just started using a Wilson seater die on an arbor press. I really like the Wilson die.
I’ll put my hat in the ring I’m at 30.8 of h4895 with 105h 25 off @2890 in a 26” bart 1-7.5 I always have slow barrels but eh it shoots very well I also fireform with 4895 29gr is what I did I use a dasher seater and whidden sizer that I trimmed a few thousands off the bottom. (Idk why I had to do that, but I did) I also bump my shoulders .003 back, it’s way smoother with the 40degree shoulder
I switched to 205m’s and picked up 10fps and cut my sd in half albeit from 8 to 4
No 109’s but I have ran 108eldm with 30.7 of h4895 (I ran a ladder) And they shot EXTREMLY well. My rifle is 7.5 bart m24 @26” I think I got 2900ish +-10fps out of it. I’m assuming you’d be close too.
What were you loading 105s to (if at all)?
I’m shooting the same load you are, but with 105s, getting 2945 FPS.
I bought 500 109s, but have not felt like doing load dev on them.
30.8 with a 105h is what I started my barrel with never saw a need to change it shot lights out, still does I think I’m at 2920 with it
as always work up but heres my data...Peterson brass is about 1 grain less capacity then lapua...
109HB .020 off lands H4895 peterson brass fed205m 26" 7.5T bartlein...only shot one each looking for pressure.
29.9g...2858
30.1g...2889
30.3g...2911
30.5g...2923
30.7g....2959...almost flat primers...would not shoot in summer
109HB .010 off lands varget peterson brass fed205m 26" 7.5T bartlein
30.7g...2895...2889...2899
30.9g...2927...2909...2906
31.1g....2929...2931...2936
31.3g...2947...2949...2949...no pressure but pretty cold when i shot these
these are the only 109s ive shot...the 105 hybrids shoot so good i never played with the 109s again...yet...
105HB .005 off lands varget peterson brass fed205m 26" 7.5T bartlein
31.3g =2965-2975
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I’ve switched all my small primer brass to fed205m it’s really made my loads way more consistent
Where you guys getting less expensive 105 hybrids? Been considering changing to 107 smk for something little less expensive.
No shit, thanks your so helpful. I get that but there is still a cost difference when you shop around. I figured this was a good forum to ask about who is finding them at the best price. Smfh
I don’t think he meant anything with his comment I don’t think anyone likes paying the high price but it’s the cost of consistency.
that said bullet central and Bruno’s are probably about as cheap as your going to find them if their in stock.
If you’re worried about $30/500 when you shoot probably a $5-8k rifle. You probably spend at least 1000$ in range and match fees annually. Your priorities are pretty backwards. The difference in Bullets is less than $150 per barrel.
