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7-6.5PRCW load data

Has anyone done some systematic testing of the White River std primers?
They've only just landed in Australia for the first time. Unfortunately my local GS couldn't get their hands on any. I've seen some measurements suggesting they're a little thicker than other primers and seat on the tight side. Other than that I don't know sorry.
 
On a separate note, my 8 twist Cheetah (button rifle barrel) would not perform consistently with the PRCW so I've pulled it and waiting to try and 8.5 twist cut rifled barrel from KS Arms. Also know of a couple of other guys who couldn't get the PRCW to work in 8 twist button barrels, but when they switched to 8.5 or 9 twist cut rifled barrels (Brux, Bartlein), it shot very well.
 
On a separate note, my 8 twist Cheetah (button rifle barrel) would not perform consistently with the PRCW so I've pulled it and waiting to try and 8.5 twist cut rifled barrel from KS Arms. Also know of a couple of other guys who couldn't get the PRCW to work in 8 twist button barrels, but when they switched to 8.5 or 9 twist cut rifled barrels (Brux, Bartlein), it shot very well.
Probably a twist uniformity problem with the button barrels or the barrel has a negative twist. I've seen button barrels where they started out as a 8 twist but by the time you got to the muzzle they ended at a 8.75.

It can happen regardless of caliber.

Button rifling displaces the material during rifling. It doesn't remove the material. If the button hits a hard spot or soft spot in the material during button rifling... it usually slows the twist down. It can speed back up to what it's suppose to be but then either way... a non uniform twist or a negative twist.
 
On a separate note, my 8 twist Cheetah (button rifle barrel) would not perform consistently with the PRCW so I've pulled it and waiting to try and 8.5 twist cut rifled barrel from KS Arms. Also know of a couple of other guys who couldn't get the PRCW to work in 8 twist button barrels, but when they switched to 8.5 or 9 twist cut rifled barrels (Brux, Bartlein), it shot very well.
G'day Willow,
I will be trying out one of Blake's 1:8.5 late this year... Hoping it will perform.
Seems okay for the 280AI he built for me..
 
They've only just landed in Australia for the first time. Unfortunately my local GS couldn't get their hands on any. I've seen some measurements suggesting they're a little thicker than other primers and seat on the tight side. Other than that I don't know sorry.
G'day Willow,
The NSWRA store has them for $240 per thousand... Not sure how stock is holding but be quick I would imagine... Been such a long drought for large rifle primers and the shop is right at Malabar.
Did you get the email from the association?
Having a bit tight fit to the primer pocket may be a good thing if they start to enlarge over time/repeated firings.
 
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On a separate note, my 8 twist Cheetah (button rifle barrel) would not perform consistently with the PRCW so I've pulled it and waiting to try and 8.5 twist cut rifled barrel from KS Arms. Also know of a couple of other guys who couldn't get the PRCW to work in 8 twist button barrels, but when they switched to 8.5 or 9 twist cut rifled barrels (Brux, Bartlein), it shot very well.
If you can get a 5r Bartlien over there Id highly recommend doing so. Especially with a touch of gain in it ;) With the 180 hyb I see no reason to ever twist it harder than an 8.5. The 9s have done a lot of damage.
 
If you can get a 5r Bartlien over there Id highly recommend doing so. Especially with a touch of gain in it ;) With the 180 hyb I see no reason to ever twist it harder than an 8.5. The 9s have done a lot of damage.
Just got my hands on a 5R 8.5 twist which landed, no gain twist though.
 
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OK a follow up range report with the 7-6.5 PRCW using N555/210M/175gr Berger Elite Hunters/once fired Lapua Brass, elevation 800 feet, temp 10C/50F CBTO 2.306"

I also had a 3 port Benchmark-Miller Brake installed, what a dream to shoot with a brake on it,

I have to say the Clymer stock is as nice a stock as Ive ever shot off the bench or freehand, I was free handing the 200 yards 8" gong consistently

57.7grs seemed to be the most consistent with velocity as well as consistently accurate this time out.

57.3- 2885,2880,2881,2884,2875,2885 100 yard group 5/8", 200 yards 1 1/4"

57.5- 2891,2894,2886,2891,2883,2891 100 yards 1/2" , 200 yards 3/4"

57.7- 2896,2895,2997,2899,2898,2899 100 yards 1/4" , 200 yards 5/8"

57.9- 2901,2907,2915,2909,2913,2919 100 yards 5/8" , 200 yards 7/8"

58.1- 2915,2915,2922 200 yard group 1 1/8" , no visual pressure signs

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Just had my KS Arms 8.5 twist barrel spun up. It's finished at 32" and is a 6 groove cut rifled affair. After barrel break in I ran ADI2209 loads (H4350) from 52.5gr up to 53.2gr. I didn't load beyond this as I just wanted to get an initial feel for the barrel. Compared to the Cheetah barrel I had which showed pressure signs at 53.2gr, the KS Arms barrel displayed no such signs, with velocity on the low side at 2835fps with Berger 184gr hybrids. This load produced an ES of 5 and SD of 1.9.

Initial testing was done at an indoor range so now that I know there were no pressure signs, I'll continue to work up a touch higher as the other guys in Australia who have got this case running well have done so around the 2850fps mark. We just don't have access to N555 and RL16/23 which produce more velocity that ADI2209. ADI2213sc bumps up the velocity, but generally speaking loses out on accuracy to ADI2209.

A little more testing on powder charge and then seating depth testing to follow.
 
Just had my KS Arms 8.5 twist barrel spun up. It's finished at 32" and is a 6 groove cut rifled affair. After barrel break in I ran ADI2209 loads (H4350) from 52.5gr up to 53.2gr. I didn't load beyond this as I just wanted to get an initial feel for the barrel. Compared to the Cheetah barrel I had which showed pressure signs at 53.2gr, the KS Arms barrel displayed no such signs, with velocity on the low side at 2835fps with Berger 184gr hybrids. This load produced an ES of 5 and SD of 1.9.

Initial testing was done at an indoor range so now that I know there were no pressure signs, I'll continue to work up a touch higher as the other guys in Australia who have got this case running well have done so around the 2850fps mark. We just don't have access to N555 and RL16/23 which produce more velocity that ADI2209. ADI2213sc bumps up the velocity, but generally speaking loses out on accuracy to ADI2209.

A little more testing on powder charge and then seating depth testing to follow.
Any further YouTube coming out? Always interesting to see the visual results of your testing.
Still going with the 100 thou jump?
 
Any further YouTube coming out? Always interesting to see the visual results of your testing.
Still going with the 100 thou jump?
Going back to basics with testing on this one - I'm close to sorting powder charge and will test seating depth in the next couple of weeks. Might try and record some of that mate. Characteristics of the KS Arms barrel look a bit different to the Cheetah, which to be fair spent most of its time being tested as I learn the cartridge. I'll be staying away from button barrels moving forward though.
 
Has anyone done some systematic testing of the White River std primers?
I picked up a brick of these on the weekend and have loaded some up for testing with my new barrel. Compared to my go to primer - S&B, the White River seat a lot firmer and I had to use a primer pocket cleaning tool to get them to seat flush. The limited reading I've done on this primer suggests it will be good so I'm interested to see whether it can match the initial load data I got from the S&B primers.
 

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