Load data for 300 PRC

View attachment 153333 Tonight's promotion for MOA rifles, Maybe they'll see this and send me a free hat!For the record I'm a First time customer from this company not a sales person, I think this thing sold itself to be honest

These custom loads are all hitting within 1-2/1000th at 3.660
It's a one and 9.5 twist! that's perfect I was thinking it was going to be at one and nine, I'd rather have a half twist worth of over stabilization than a half twist worth of under stabilization. I don't have a chamber gauge in this caliber, I plan to shoot this weekend and use 2 spent cases to make a chamber length Gage and another one to check ogive to thread contact distance.

Their test target shows .532 outside edge minus .300 for a .23 group. That's really exciting I have another rifle they can hold an eighth of a minute accuracy.


I'm experiencing similar groups with the Berger out of my rifle. H1000 and RL26. 1/10 twist, LH blue printed 700 action with proof barrel.
 
Yeah.. You're right on the 1:9 vs 1:9.5
I was thinking upsidedown or backwards. I was running a bunch of numbers in one of the online stabilization calculators looking the velocity Sweet spot with 225's. After about an hour playing with that I couldn't remember my own phone number
 
Yeah.. You're right on the 1:9 vs 1:9.5
I was thinking upsidedown or backwards. I was running a bunch of numbers in one of the online stabilization calculators looking the velocity Sweet spot with 225's. After about an hour playing with that I couldn't remember my own phone number
I only replied because a dealer I know of was selling the higher number is more to people. He actually built a 10tw 28 nosler claiming to be running the 195's at 3200fps and a bunch of other bold claims about his building prowess.
One of those smile and run away when they turn around deals.
 
RL26 gave me that kind of speed out of my win mag pushing 212's, but it seemed temp sensitive to me. Groups were a little inconsistent. H1000 seems to work better (for me) in both the win mag and the prc. Glad to see someone making RL26 work!
Sorry. Don't know what I was thinking here. The powder I was thinking about was RL22! Just got my hands on a pound of RL26.
 
I had built a version of the prc before it was released. In short its 40deg shoulder with same taper and an oal of 2.59 instead of 2.58. Id been using blown out adg 300 win mag brass at 79gr of retumbo. This load has performed for me out to 1910 yards very well.

I ran out of brass and just bought hornady prc brass. Its 10gr heavier than the adg brass i converted. I had to back my load off to 73gr of retumbo to be able to lift the bolt after COW fireforming to my chamber. Not sure if its the brass or what but i gave everything a good scrubbing and brass prep checked. Still hanging in there with 73gr as a max charge. I can shoot these with my adg brass with a different load and they fly the same out to 800yrds today at the range.

Kinda weird.....
 
I had built a version of the prc before it was released. In short its 40deg shoulder with same taper and an oal of 2.59 instead of 2.58. Id been using blown out adg 300 win mag brass at 79gr of retumbo. This load has performed for me out to 1910 yards very well.

I ran out of brass and just bought hornady prc brass. Its 10gr heavier than the adg brass i converted. I had to back my load off to 73gr of retumbo to be able to lift the bolt after COW fireforming to my chamber. Not sure if its the brass or what but i gave everything a good scrubbing and brass prep checked. Still hanging in there with 73gr as a max charge. I can shoot these with my adg brass with a different load and they fly the same out to 800yrds today at the range.

Kinda weird.....

I have 230 some odd pieces of hornady .300 PRC, 190 some odd from the same lot. Out of that large lot the case weights were no way to sort them. I did weight and then volume after the 3rd firing and trimming to length. Cases within a 0.1 grain weight within a group had volume variances of a few or more grains of H2O. I sorted my cases by volume for loading. At the 2nd firing of most cases I started seeing and marking sticky cases. About 35% of my cases were sticky. KEEP IN MIND I was shooting OCW, but I had sticky cases occurring at random, some down around 72 grains H1000 and some at the top which was 80.5... those above shot above 78 grains were chucked in the round file, which is why the odd number of cases.

Several people have reported sticky .300PRC brass... I am waiting for better brass before I shoot my rifle anymore... So... essentially i have 230 something pieces of scrap brass with 1-4 firings.

Edit: All of the brass is still usable and still has tight primer pockets etc... I'm just not going to keep developing loads with it, or I will cherry pick the best brass that doesn't stick and make disposable hunting ammo from it.
 
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Interesting. I just turned necks again to check, turns out there was some weird brass flow during fireforming, in my chamber remember.

I turned necks before fireforming then started load work up and had early signs of pressure. I turned necks again and took quite a bit of brass off again where the donut would be. I fired a couple round with a higher charge and it was fine! Made it to 77gr and thats where it was about what i would call max.

Lesson learned.
 
Yup saw that. We will see when it makes it up here
You have to go to their website and find the 300PRC brass and get on their list. They're going to do small runs so 50 pcs is going to be like $88...if you want it, get on the list. It should be available soon. They say within the first quarter of the year.
 
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