210 VS 215 Berger Question

[samson]

Good Morning. I have a Seekins PH2 chambered in a 300 PRC and thought i had a decent load developed with the 215's. I was shooting them over N570 (82.5) and getting 2945 FPS. I recently went back to the range to tweak them and the groups were all over the place. The ES and SD were still low but not sure what caused the issues. I then had some 210's left over from my 300 WM and tried them. Berger suggested with H1000 to start at 81 and go up to 85.7. I loaded up 9 rounds at .5 increases and shot over a chrono. 81 already showed 3011fps and I stopped at 84.5 (Ejector Mark) and it was up to 3156fps. Am I wrong thinking this is crazy fast for that bullet? I did find a plateau in speeds from 82-83. Is anybody else shooting the 210's with H1000 in a PRC?

 

[ARlife4me]

What barrel length?

 

[ontarget7]

I would say your pushing compressed loads at 82-83 grains with 210's depending on seating depth. At 85.7 grains I'd but your way over pressure

 

[samson]

26" Barrel.

 

[samson]

Started compressing around 84

 

[Shane Lindsey]

Were the 215s shooting well with virgin cases or fireformed?

If you are on the edge of pressure with virgin cases, you may be overpressure with fireformed.

I have had good virgin loads and the tried reloading and neck tension (even though measured same as virgin cases) was causing issues. Lapua cases using Redding bushing dies.

Load a fireformed case as normal. Once seated, try and push the bullet in a fireformed case with bare hands. This was my issue. Not getting enough neck tension on the fired cases when sizing.

 

[ARlife4me]

It's about par on velocity depending on coal. When compared too 300wm the velocity your getting makes sense. but as @ontarget7 stated it could be over pressured? I don't have any prc chambered guns. OP could be happening before signs start too show, but it could be just slightly over at that time? I have a C6 30" 300wm barrel 1/9 that I'll use only 215gr and up. The local gunsmith moved away, so trying too find someone close for quality work. Hoping too get over 3k with some berger 230gr or close too that velocity. Hopefully I'll have enough n570 for my 264wm, 300wm and 338lm builds. Might have too use 869, lrt, 4000, 33, n170, n568, but not sure about 8133, 7977 or 7828.

 

[Shane Lindsey]

I was getting 2950 with N570/215 with a 26" Proof 300 WM in Norma cases. You should be close with a 30" tube for sure.

It's about par on velocity depending on coal. When compared too 300wm the velocity your getting makes sense. but as @ontarget7 stated it could be over pressured? I don't have any prc chambered guns. OP could be happening before signs start too show, but it could be just slightly over at that time? I have a C6 30" 300wm barrel 1/9 that I'll use only 215gr and up. The local gunsmith moved away, so trying too find someone close for quality work. Hoping too get over 3k with some berger 230gr or close too that velocity. Hopefully I'll have enough n570 for my 264wm, 300wm and 338lm builds. Might have too use 869, lrt, 4000, 33, n170, n568, but not sure about 8133, 7977 or 7828.

 

[samson]

They were fire formed loads. I may have to try different seating depths. They were .050 off.

 

[ARlife4me]

My ocpd is loading to where only the boat-tail is in the shoulder just behind the neck when possible. With mags @ 3.850" it gives me options. Every caliber I own I have uni-throaters for all.

 

[ontarget7]

.08 range has worked well for me on seating depth, more forgiving with tighter vertical group spreads

 

[MagnumManiac]

I would say your pushing compressed loads at 82-83 grains with 210's depending on seating depth. At 85.7 grains I'd but your way over pressure

What difference does it make if the load is compressed?
Are you insinuating that pressure is going to be excessive due to compressed powder charges?
If you are, then it is false.
Compressing the powder doesn't change peak pressure in all but very few specialised powders.
Trail Boss is one that comes to mind.

Cheers.

 

[ontarget7]

What difference does it make if the load is compressed?
Are you insinuating that pressure is going to be excessive due to compressed powder charges?
If you are, then it is false.
Compressing the powder doesn't change peak pressure in all but very few specialised powders.
Trail Boss is one that comes to mind.

Cheers.

I'm not insinuating anything other than direct experience with the cartridge and the 210's.

So if you have something useful to add by all means go for it. I'm always willing to test new loads.

 

[MagnumManiac]

I'm not insinuating anything other than direct experience with the cartridge and the 210's.

So if you have something useful to add by all means go for it. I'm always willing to test new loads.

What experience is that?

Cheers.