quick 6BRA load test

[comagutsa]

well the time has come and I'm in desperate need of a load but the weather in western Australia hasn't been helping.
I have done a few test but wind or mirage hasn't given me the best results and with my state 500m fly titles coming up I bit the bullet and something is better than nothing, I normally like testing at 300m

yesterday I had bugger all wind (less than 10km/h but dropping off to bugger all at times) but it was a 38 degree C day 100f.
I set up and could only put target at 100m because of mirage.. I waited hours but some clouds came over for 30mins and mirage disappeared so I got my shots in
105gr hybrids at .008 jam with 2206h/H4895 with .003 neck tension and cci450
looks like 31gr is a winner
31.2gr was shot on a hot barrel and 31.3gr was shot an hour later as clouds disappeared and mirage came back .
31gr and 31.1gr where 3011fps and 3012fps avg
31.2gr 3021fp
31.3gr 3033fps
forgot to arm labradar 30.9gr

I then had a few made up in 31gr for a quick seating depth test .. I used the 31gr in load test as my .008 jam
but I will be testing .020 and .024 jump next as they flattened out from .012 and .016 jump..
speeds where 3010fps for jammed down to 2995fps .016 jump
just hope to test 31gr with .006 jam or .020 jump at 500m soon

 

[Willow]

I would back off to 30.8gr or 30.6gr and try the 008 jam and .020 jump. Your velocity will be fine, keeping it around the 2970-2990 mark is where I feel this cartridge is at its most effective and will keep you at safe pressure levels. Based on my experience with the BRA so far, you don't need to run it above 3000, there's nothing to be gained from 30-40fps and you don't want pressure problems hitting you in the State Championships.

Yesterday's heat was bloody shocking, but it was the calmest day we've had in months! Should be a good battle between yourself and Rushty!

 

[RDavies]

How about, on the way between .006" jam and .020", try 0.010" jump as it is what seems to work for quite a few people running the 105 Hybrids.

 

[comagutsa]

I would back off to 30.8gr or 30.6gr and try the 008 jam and .020 jump. Your velocity will be fine, keeping it around the 2970-2990 mark is where I feel this cartridge is at its most effective and will keep you at safe pressure levels. Based on my experience with the BRA so far, you don't need to run it above 3000, there's nothing to be gained from 30-40fps and you don't want pressure problems hitting you in the State Championships.

Yesterday's heat was bloody shocking, but it was the calmest day we've had in months! Should be a good battle between yourself and Rushty!

willow my speeds are all over the place atm .. i used 31gr on weekend and they were only 2970 fps the same load this day and same bullets left over where 2995fps , the only thing different was labradar was closer to the end of barrel, about 3cm than what i had it on the weekend about 10cm behind end of barrel
didn't think the temperature would of made that much difference to powder...or could it?, were low 30s on Saturday
used the same chargemaster the trickled up on my 505 scales ??

i have attached a pic from a few weeks ago with the speeds i got and have always been round there (this test was .002 neck tension and .008 jump) ... the test this week was the fastest i have had and i'm not sure why

and yeah Rusty is going down hahaha

 

[comagutsa]

willow i did pull this out on my 3rd round at 500m , 31gr with .008 jam and .003 neck tension and LR was saying 2970fps ES 9 , wind and mirage cam in so i rattled them down

 

[KenOath]

willow my speeds are all over the place atm .. i used 31gr on weekend and they were only 2970 fps the same load this day and same bullets left over where 2995fps , the only thing different was labradar was closer to the end of barrel, about 3cm than what i had it on the weekend about 10cm behind end of barrel
didn't think the temperature would of made that much difference to powder...or could it?, were low 30s on Saturday
used the same chargemaster the trickled up on my 505 scales ??

i have attached a pic from a few weeks ago with the speeds i got and have always been round there (this test was .002 neck tension and .008 jump) ... the test this week was the fastest i have had and i'm not sure why

and yeah Rusty is going down hahaha

Law of averages says the more you loose the closer you are to a win... your long overdue for a win

 

[comagutsa]

hahahaah

 

[newbieshooter]

willow my speeds are all over the place atm .. i used 31gr on weekend and they were only 2970 fps the same load this day and same bullets left over where 2995fps , the only thing different was labradar was closer to the end of barrel, about 3cm than what i had it on the weekend about 10cm behind end of barrel
didn't think the temperature would of made that much difference to powder...or could it?, were low 30s on Saturday
used the same chargemaster the trickled up on my 505 scales ??

i have attached a pic from a few weeks ago with the speeds i got and have always been round there (this test was .002 neck tension and .008 jump) ... the test this week was the fastest i have had and i'm not sure why

and yeah Rusty is going down hahaha

Just wondering - how many rounds down your barrel so far?

 

[comagutsa]

Just wondering - how many rounds down your barrel so far?

394 rounds .

 

[Willow]

willow my speeds are all over the place atm .. i used 31gr on weekend and they were only 2970 fps the same load this day and same bullets left over where 2995fps , the only thing different was labradar was closer to the end of barrel, about 3cm than what i had it on the weekend about 10cm behind end of barrel
didn't think the temperature would of made that much difference to powder...or could it?, were low 30s on Saturday
used the same chargemaster the trickled up on my 505 scales ??

i have attached a pic from a few weeks ago with the speeds i got and have always been round there (this test was .002 neck tension and .008 jump) ... the test this week was the fastest i have had and i'm not sure why

and yeah Rusty is going down hahaha

It's interesting that your speeds have varied like that, for example your 30.7 and 30.9 loads have great ES/SD but 30.8 suddenly has a spike in it...I would not have thought a node would open up like that with only .1gr variation. How confident are you with the Chargemaster/balanced scale combo? Until I bought some A&D scales last year I was relying on a Lyman Gen 5 electronic powder/scale combo. I have no doubt it was having an effect on ES/SD when trialing a couple of loads over a friend's Labradar I'm now using a Chargemaster Lite with the A&D scales (just using a pair of tweezers to add/remove individual granules as necessary) and over the course of loading 25-30 rounds will see as much as 0.4gr difference between charges. The A&D has made a huge difference in eliminating that and the Labradar figures are backing it up.

The increased temperature may have had some input into it...how long was your rifle and ammo out for? Ground temp could have been over 40c, particularly if you were shooting off a concrete firing line. I haven't played around with my Labradar enough to see if placing it closer to the end of the barrel makes much of a difference. I don't see why it would.

 

[comagutsa]

It's interesting that your speeds have varied like that, for example your 30.7 and 30.9 loads have great ES/SD but 30.8 suddenly has a spike in it...I would not have thought a node would open up like that with only .1gr variation. How confident are you with the Chargemaster/balanced scale combo? Until I bought some A&D scales last year I was relying on a Lyman Gen 5 electronic powder/scale combo. I have no doubt it was having an effect on ES/SD when trialing a couple of loads over a friend's Labradar I'm now using a Chargemaster Lite with the A&D scales (just using a pair of tweezers to add/remove individual granules as necessary) and over the course of loading 25-30 rounds will see as much as 0.4gr difference between charges. The A&D has made a huge difference in eliminating that and the Labradar figures are backing it up.

The increased temperature may have had some input into it...how long was your rifle and ammo out for? Ground temp could have been over 40c, particularly if you were shooting off a concrete firing line. I haven't played around with my Labradar enough to see if placing it closer to the end of the barrel makes much of a difference. I don't see why it would.

I have a FX 120i and a v2 auto tickler stuck in bloody customs atm.. been in their since friday arvo.. and hasn't moved .. only took 3 days from Canada and i paid express post to.. hurry up dam it haha i can't wait to use it
My gun and ammo were out for hours on the bench under the roof waiting for conditions so ammo might of got hot

 

[Willow]

I have a FX 120i and a v2 auto tickler stuck in bloody customs atm.. been in their since friday arvo.. and hasn't moved .. only took 3 days from Canada and i paid express post to.. hurry up dam it haha i can't wait to use it
My gun and ammo were out for hours on the bench under the roof waiting for conditions so ammo might of got hot

If that's the case then I suspect you may have pre-cooked that ammo a little bit given the heat...It was definitely hot enough. I once made the mistake of keeping a 280AI loaded round in the chamber for a couple of minutes waiting out a wind shift in a barrel which was definitely on the warm side...when I eventually pulled the trigger she flew high. Won't make that mistake again!

 

[pat fulghum]

What length barrel?

With my 30” it seems 2995-3000 is the range

 

[comagutsa]

What length barrel?

With my 30” it seems 2995-3000 is the range

28 inch mate but like willow said i think the heat got to my loads causing them to speed up

 

[urbanrifleman]

I keep watching these BRA threads and that H4895 in this cartridge looks super jumpy compared to a standard 6BR with R15 or Varget, and you end up with only about another 100 fps of velocity in the end.

 

[JMayo]

30.5 varget was mine best. Also 30.8.
All other wouldn't group.
Bartlein 8 twist.

 

[BradY]

Barrels will like what they want. Don’t be afraid to change things up mate. Primers too. Try br4 and federal gold match. H4895 doesn’t need a magnum primer to spark it off. My dasher that shot really well (when the recoil lug was bottomed out hard due to a bad bedding job) used br4’s and 2206h. Cci450 didn’t work that well.

 

[KenOath]

Yep trying different primers is a must once you’ve found a powder charge and seating depth that works. I shot these 4 x 5 shot groups at 400m in good conditions, 31gns 2206H, 5 Jam, Berger 105H. Unfortunately the 400s pierced 6 out of 15 so tweeked the seating depth to 8jam with the 450s which tightened it up and was good to go.

 

[comagutsa]

I finally got a good day to test .. dam the node is small . Will test 30.8 to 31gr to fine tune
300m with 2206h/H4895 105gr hybrids. 015 jump, cci 450s .002 neck tension. 28inch kreiger 1:7.5 twist

 

[Alex Wheeler]

I would tighten the neck tension up a bushing size and drop the hybrids. BR4 or 400 with H4895. If your piercing 400s, your gunsmith can fix that.