6mm/6.5 PRC Load Recommendations

[mullmann03]

Both H1000 and H4831SC work well. Just don't expect a close to maximum load at 60 degrees to be good at +90. Gonna get some clickers and possibly out of a good node a bit.
FWIW, Just using Whidden 6.5 PRC bushing dies.

My 25prc loads are both in the 57 and 57.5 range

 

[mullmann03]

My barrel should be here Saturday so hopefully Sunday I can go test some loads.

 

[.300 Dakota]

They were thinking about starting on mine a week or so ago and ran into an issue with what I ordered. Got on the phone and got it clarified without missing a beat. No eta, though. I didn't ask.

 

[mullmann03]

I loaded up 58,58.5 and 59gr of N565 and 57,57.5 and 58gr of H1000 to test. I am running 58gr of N565 and 57gr of H1000 in my 25PRC with 135 Bergers.

 

[.300 Dakota]

I'm going to go a bit slower. My 6.5 PRC did VERY well with Magnum, so I see no reason N568, LRT, and StaBall HD shouldn't work equally as well in the 6mm version. Only issue is I'm limited to a 24" barrel, so I may wind up using Grand or MagPro and compromise a bit.

FWIW, H4831SC may be the best choice of burn rates for the 24" barrel, however. I still have some MRP to throw in, also.

 

[Wilderness Blacktail]

I'm going to go a bit slower. My 6.5 PRC did VERY well with Magnum, so I see no reason N568, LRT, and StaBall HD shouldn't work equally as well in the 6mm version. Only issue is I'm limited to a 24" barrel, so I may wind up using Grand or MagPro and compromise a bit.

FWIW, H4831SC may be the best choice of burn rates for the 24" barrel, however. I still have some MRP to throw in, also.

My 6.5PRC 22" 8twist did ok with Magnum, not bad, same with H1000 and IMR7977, so I went faster and tried H4350 and got better speeds and accuracy. Then tried A4350 and that was the one. This was primarily with monos 122-127gr but some heavy eldms as well. This has worked out the same in my 270WSM as well. Jus somethin to keep in the bullpen.

Incidentally Ive had 3 rifles where a 127LRX and 147ELDM took same charge of the same powder as max load. I figure its that loong bearing surface on the mono.

 

[.300 Dakota]

My 6.5PRC 22" 8twist did ok with Magnum, not bad, same with H1000 and IMR7977, so I went faster and tried H4350 and got better speeds and accuracy. Then tried A4350 and that was the one. This was primarily with monos 122-127gr but some heavy eldms as well. This has worked out the same in my 270WSM as well. Jus somethin to keep in the bullpen.

Incidentally Ive had 3 rifles where a 127LRX and 147ELDM took same charge of the same powder as max load. I figure its that loong bearing surface on the mono.

Yeah the LRX seems to lack one or two of the grooves of the TSX/TTSX, so there is more bearing surface there, even compared to other Barnes bullets. I also attribute it to increased stiffness of the mono. I believe it creates a bit more inertia to overcome. Kind of like falling off a balcony and hitting the ground vs hitting concrete. Both are bad, but concrete is definitely worse. There's a bit of give or spring back or something. While you won't see an imprint on the ground unless it's really soft or your balcony is really high, the hardness is way less than concrete. Same idea with the lead core and thin jacket vs monolithic. Even when Barnes just made the original X without grooves. Bearing surface was same as other bullets with similar design like a flat-based Hornady or Speer, but they would take nowhere near as much powder to reach max pressure. Even a bullet that is MOSTLY monolithic with a little lead bonded in the frontal core (ala Bear Claws, and to a lesser degree, A-Frames) will max out on pressure with less powder (and speed) than other cup and cores.

Now, I shot 140gr Ballistic Tips and 120gr Ballistic Tips in my 6.5 PRC with 1:8 26" Bartlein. I had to seat deeper in the case than you with your 143 Hornady. I was very disappointed in speed with mine, and accuracy wasn't very good until I tried Magnum in a recommendation by somebody on this forum, I believe. Gave some of my best velocity and WAY better accuracy with the traditional bullet styles.

There are so many factors to consider in the dynamics of handloading, it's nearly impossible to consider them all for every application. Seating depth, neck tension, bearing surface, twist to some degree, possibly metallurgical properties of the bullets loaded (and barrel), bullet weight, case capacity, powder volume, ambient conditions, and primer heat when fired ALL affect pressure and velocity to some degree. I'm sure there are more things, these are just a few off the top of my head. Chamber dimensions is another. See, I missed one. Bore fouling - missed another... you get my point. I should probably start back over back at the 4350 rate of burn and go slower to find the new sweet spot for the bullet I finally decide to use. I appreciate you making me rethink this. Whenever I think I have it figured out is precisely when I don't!

 

[Wilderness Blacktail]

Yeah the LRX seems to lack one or two of the grooves of the TSX/TTSX, so there is more bearing surface there, even compared to other Barnes bullets. I also attribute it to increased stiffness of the mono. I believe it creates a bit more inertia to overcome. Kind of like falling off a balcony and hitting the ground vs hitting concrete. Both are bad, but concrete is definitely worse.

I should probably start back over back at the 4350 rate of burn and go slower to find the new sweet spot for the bullet I finally decide to use. I appreciate you making me rethink this. Whenever I think I have it figured out is precisely when I don't!

Good analogy on the monos pressure/drag.

If you do start with that burn rate n go up youre going to have a nice thorough data set, thatll help lotta folks in the future.

When I got mine there wasnt any pressure tested data published yet, at least not with monos, just forum posts, some blog posts and a video by that one gent in the black cowboy hat who reps a magazine? Its amazing how much we the shooting world can learn in a few years time.

 

[.300 Dakota]

I'm having issues getting started with forming brass. I used what I had onhand, which was 50 new pieces of Nosler I bought a year plus ago from a guy selling it without a box. What I got are apparently culls. I didn't realize this until I started trying to form rounds only to find the necks several thousandths out on the concentricity gauge. When I checked the new rounds out of the bag, every single one was .005" out.

I have now ordered Peterson, which should be delivered by week's end. I got to practice a bit with the Nosler, and ran it through an RCBS .289" bushing first, then a SAC .280", and finished with a Forster .272". I tried a .268" first, but it was WAY too tight to expand the necks back with a 6mm expander. The .272" was about right, and didn't require excessive pressure on the ram to expand. Unfortunately, the Peterson brass will likely be different, and require yet another size of bushing. I was able to make a finished case with the Nosler brass that was the same .005" out as what the 6.5 virgin piece was I started with. That means I can do it; I just need the right size of bushing and good quality brass.