300 PRC SHERMAN IMPROVED

[BoatTail]

Take a look at Rhovee's thread on his 30-28 Nosler build. It's interesting that he said that RL33 and N570 worked best for 28 Nosler but he used H1000 for his load test for his 30-28. I used RL33 in my 28 Nosler and 88 gr gave ~3226 fps. I settled on 87 grs for 3152 fps as an accuracy load with no excess pressure.

I tried RL33 in my 30-28 but could not get enough in there to get the pressures needed. I ended up using RL26. This may help you with your 300 PRC SI load testing as you consider powers to use. Here is his thread with load data and results:
https://www.longrangehunting.com/threads/30-28-nosler.201557/

From what I see both the 300 PRS SI and 30-28 Nosler are excellent wildcats and both should be almost identical for both FPS and accuracy with the proper neck and freebore. I'm excited to see where this all goes.

 

[elkaholic]

Here's where to start in your S.I.
RL 33/225 ELDM. (28" barrel)
Start .84@2925 '. Max 89-90 @3100
N570. 81@2950' . Max.85 . @3100'
IMR 8133. 80@2850' .max 84 . @3050'
215 Berger . Start 1 grain higher
Max about 100' faster
I used WMR primers

 

[FURMAN]

You ought to have a contest to rename it. It deserves a cool name. Plus saying PRC SI is a mouthful.

 

[elkaholic]

You ought to have a contest to rename it. It deserves a cool name. Plus saying PRC SI is a mouthful.

We could just call it a "prissy" but it's not
I did that because when everyone converts their prc barrel, they can just stamp an S.I. behind it!!

 

[FURMAN]

Those numbers are crazy. The 30 Nosler will not do that. Are primer pockets lasting at those max charges? Any accuracy testing yet?

 

[elkaholic]

Those numbers are crazy. The 30 Nosler will not do that. Are primer pockets lasting at those max charges? Any accuracy testing yet?

Primers won't last at those loads. Probably 2 firings. I can run around 3050' and get about 4-5 loads

 

[FURMAN]

Primers won't last at those loads. Probably 2 firings. I can run around 3050' and get about 4-5 loads

With 225s?

 

[elkaholic]

With 225s?

Ya, I can run the 225's up to 3050' without dumping primers but Mine has a 28" barrel. I think realistically, 3000' is about a working max with a 26".

 

[Weatherby Fan]

Ya, I can run the 225's up to 3050' without dumping primers but Mine has a 28" barrel. I think realistically, 3000' is about a working max with a 26".

Hey Rich have you tried R26 at all ?

 

[elkaholic]

I think I did a couple years back and it was ok. I think the slower powders are better though and N570 is more temp stable as well as IMR 8133. 8133 had a higher es than I like though.
H1000 will give you a good load but less velocity. If you wanted to run the 225's in the mid 2900's, it would be a good choice.

 

[elkaholic]

Rifle came back today. Hope to shoot it tomorrow before the weather hits and get some initial data on how the prc cases shoot in my chamber. Stay tuned!

 

[ramrod79]

Oooo dog that's a nice rig Rich!!

 

[elkaholic]

Oooo dog that's a nice rig Rich!!

thank you! I will likely cerakote it or?? My barrel that I just took off was nitrided and I don't like the shiney Stainless!
I had to cut the barrel channel quite a bit. My old barrel was a Sendero and this one is a heavy varmint. Emphasis on the HEAVY!!
Oh well, its a stand rifle and I don't intend to pack it too far. It weighs around 13 1/2 lbs according to the bathroom scale. 28" 5r Bartlein 9 twist with 5 port Pierce brake

 

[Idaho Trecker]

Sweet looking rig!!! I wish I had tomorrow off work and I'd come help you shoot that beast