6BRA load data

[newbieshooter]

Got out today on new barrel and was surprised how fast it was running from a 26 inch 1:7 kreiger.
Fire forming load was 28.5gr 4895 w cci 450's.
109 hybrid 5k off the lands. was shooting 2815fps
same load but with some leftover 105 RDF's to burn up was running 2851fps

Formed cases I took 12 rounds (6x2) and chrono'd up a ladder with the 109's in the range most guys are ending up for charge and 15k jump to start:
30.1gr - 2931
30.2gr - 2936
30.3gr - 2949 w/ firing pin starting to crater occasionally
30.4gr - 2949 w/ primers def cratering just a little
30.5gr - 2970 w/ primers starting to look beyond what i'd want to see
30.6gr - 2968 w/ primers, ejector shine, and bolt a little sticky.

Unfortunately - with additional 3 shot groups of the .1, .3, .5 loads none of these shot well.

Not sure if the 109 is a little too heavy for 4895, or why I'm running to fast and hot versus lot of other guys.

Will get out again and test 29-30 and hopefully something down there will tighten up.

Anyone else running 109's? Varget (slightly slower) might be a better choice for them and fill the case better?

For the heavies (109/110s) I usually start with Varget first.....

 

[johara1]

I have shot 6bra in 1000yd benchrest for a few seasons now. I had a model7 Remington rebarrelled to 6bra factory contour 18” 8twist barrel. I had this rifle fixed for my 9year old to shoot some deer with. I will be shooting 95-100gn bullets.
Anyone have any recommendations on a good speed powder for this short barrel? With powder hard to find at the moment any recommendations? I have saw CFE223 mentioned also think AR Comp may fit. Any more recommendations in case I can’t find either of those. I have H4895 and R15. I am just thinking something different may shine in this short barrel.

I would try 8208 XBR in a short barrel..... jim

 

[JFrank]

I’m not sure why this happened today, getting heavy clickers as well.
6 BRA
30.9 gr H4895
108 Berger
450 primer
Anybody have any ideas ?

 

[Alex Wheeler]

If you're getting clickers you need a different die. Which one are you using? I think you are running a bat action? Check your firing pin fall and replace your spring. If its the old style firing pin assembly get the new style and I prefer the heavy Spring.

 

[JFrank]

@Alex Wheeler
I’m using the Harrell’s 2.5 Dasher -.85
I have a honed Wilson for comparison.

Headspace/ bump bye my tools is .002

The action is the Bat B

FP is recent as per the builder however I’m not sure what style.

This older lot of powder may just be Nuclear!!

I can drop a full grain and work back up using a fresh lot number.

I could switch dies also but prefer to do one thing at a time.

I appreciate your thoughts Alex

 

[Alex Wheeler]

Get a Harrell's #3 BRA die. If you post a pic of the f pin assm. I can tell if its the new or old style. Push the pin down on a bathroom scale and see what the spring measures.

 

[tom]

I’m not sure why this happened today, getting heavy clickers as well.
6 BRA
30.9 gr H4895
108 Berger
450 primer
Anybody have any ideas ?

I haven't shot 108s in the BRA, so possibly @Jet may see this and correct me if I'm wrong. But in the dasher years, I could never run the 108s up where I could with the lower bearing length options. Like nearly a grain worth of difference. Die/chamber fit probably is some of the "clicker" problem...but I'd guess it's to hot as well.

Tom

 

[Jet]

Jim

Drop your powder down. Start around 29.6gr and go up in .02gr increments until you see pressure (which you already did). Get them shooting around 2920 and you will find a flat spot. If you continue to run them hot then you will need a 3.0 Harrell’s

 

[JFrank]

Thanks fellas,
Jeff
Dusty
Lincoln
Alex
Tom
Rich

I’m on it.. Alex I’ll check that FP
and report back.

Much Appreciated
Jim

 

[JFrank]

Oh’
I almost forgot the reason I was at the range was mounting a new scope and first few shots getting on paper at a hundred.

 

[Evan]

Oh’
I almost forgot the reason I was at the range was mounting a new scope and first few shots getting on paper at a hundred.

You've got some vertical in that group. Definitely too hot

 

[JFrank]

I was able to get the pin assembly out but how do I get it back together ?
Lol
It takes 22 lbs of pressure to compress
@Alex Wheeler

 

[Ccrider]

View attachment 1202455
I was able to get the pin assembly out but how do I get it back together ?
Lol

Send it to Alex.

 

[Alex Wheeler]

Push it in and turn. You have the new style with light spring. I'm surprised you had that crater, I bet theres drag on the pin or low fall.

 

[JFrank]

I got it’

Yeah I’ve not seen the craters stand up like little golf tees before.

I’ll take another shot at it this week then report back.
J

 

[Jet]

Jim

For future reference, BAT has some videos on their website that can assist with disassembly/assembly, etc.

 

[bpmoss1]

Ran in my new 6bra 28" 8tw HV Ledderer barrel ( w/ magneto-speed) that @Alex Wheeler fit and chambered for me. I can't believe it settled down so fast, I thought it would take 60-80 rounds but appears it only took 3, see pic. Used 31.0 rl-15. 1 and clean for 5, 5 and clean for 5 and 10 and clean til done. Seems like a pretty fast barrel. As the day got hotter so did the load. Noticed the bolt lift increasing and light cratering. Barry.

 

[bpmoss1]

@Alex Wheeler Did 2 ladders @600 today (my first time tuning this way) you guys tell me your thoughts and where to go next. Also, is this showing positive compensation with 8 at the top of barrel swing, as it repeats on both tests ( .005 in and .005 out?Thanks, Barry.

 

[JFrank]

The speed is very impressive, I’m curious how you got there.
I can’t get close without pressure.

 

[bpmoss1]

The speed is very impressive, I’m curious how you got there.
I can’t get close without pressure.

This barrel seems faster than my 2 Kriegers for sure. @ 31.6 H4895 I begin to feel a little stiffness in bolt and more so @ 31.8. Also slight cratering. I dont want my load to be up there.