6.5 PRC Discussion

I'd try a different bullet, my 6.5x284 does not like the 143 ELDX, best I can get is about .75moa, burger 140 hybrids shoot .25 MOA. In my case I believe it's the longer bearing surface as I can't keep the pressure ring out of the should neck junction with the 143's. For speed go with RL 26.
 
Did you Chrony the test loads?
Did you eliminate shooter error?
1) I did chronograph test loads - Magneto Speed
2) I believe I was rock solid off of shooting bags - in reality, I barely hold onto the rifle.

One thing I learned many years ago while trying to reload for a Model 70 Featherweight, barrel temperature was crucial on thinner type barrels. It's tough to shoot "multiple strings" AND control temperature. (Ultimately, my Model 70 now has a fluted Bartlein on it now) 👌
 
I apologize in advance for the lengthy explanation!

I've read EVERYTHING on LRH regarding 6.5 PRC loads, BUT I'm reloading for my friend's 6.5 PRC (Christensen Arms) and have struggled helping him develop a good load. I tried talking him to a 7 MAG, but he had to go with the latest and greatest😳

Equipment - A&D scale, Wilson Bullet Seater, (borrowed some Lee Dies - Redding dies on order)
100 rounds down the tube so far
COAL: 2.940
Brass: Nosler (blems)
Bullet: Hornady 143 ELDX
Primer: FED 215M (also tried WIN LRP - no difference)
Powder: H1000 (55.0 to 57.0) no exceptional groups, developed pressure very early (~2880 FPS)
Powder: IMR8133 (56.0 to 57.5) .75/1.0 MOA, but FPS ~2800 range, loaded hotter but developed heavy bolt lift
Powder: IMR4831(47.5 to 49.5) at 49.0 shot 1/2" MOA ( AVG FPS @ 2841). Starting to develop heavy bolt lift

Side note - I shot 3 rounds of factory ammo (.7 MOA) and shot 1 round for velocity (3010 FPS). Hornady Precision Hunter 143 ELDX. I thought I could get close to duplicating this, but so far it's a no go. I'm sure I'm not the first to disassemble a factory load and find there is 54.84 to 54.86 of some type of powder, but it is definitely a mixture of powders. (Black powder with sprinkles of brown kernels, approx. 1 grain = .02)

Opinions/suggestions Welcomed😀. Should I just tell my friend to shoot factory ammo? He said he can't find any! I said there's plenty of it for sale on Gunbroker👍
 
I apologize in advance for the lengthy explanation!

I've read EVERYTHING on LRH regarding 6.5 PRC loads, BUT I'm reloading for my friend's 6.5 PRC (Christensen Arms) and have struggled helping him develop a good load. I tried talking him to a 7 MAG, but he had to go with the latest and greatest😳

Equipment - A&D scale, Wilson Bullet Seater, (borrowed some Lee Dies - Redding dies on order)
100 rounds down the tube so far
COAL: 2.940
Brass: Nosler (blems)
Bullet: Hornady 143 ELDX
Primer: FED 215M (also tried WIN LRP - no difference)
Powder: H1000 (55.0 to 57.0) no exceptional groups, developed pressure very early (~2880 FPS)
Powder: IMR8133 (56.0 to 57.5) .75/1.0 MOA, but FPS ~2800 range, loaded hotter but developed heavy bolt lift
Powder: IMR4831(47.5 to 49.5) at 49.0 shot 1/2" MOA ( AVG FPS @ 2841). Starting to develop heavy bolt lift

Side note - I shot 3 rounds of factory ammo (.7 MOA) and shot 1 round for velocity (3010 FPS). Hornady Precision Hunter 143 ELDX. I thought I could get close to duplicating this, but so far it's a no go. I'm sure I'm not the first to disassemble a factory load and find there is 54.84 to 54.86 of some type of powder, but it is definitely a mixture of powders. (Black powder with sprinkles of brown kernels, approx. 1 grain = .02)

Opinions/suggestions Welcomed😀. Should I just tell my friend to shoot factory ammo? He said he can't find any! I said there's plenty of it for sale on Gunbroker👍
Looks like a helluva group to me!
 
I apologize in advance for the lengthy explanation!

I've read EVERYTHING on LRH regarding 6.5 PRC loads, BUT I'm reloading for my friend's 6.5 PRC (Christensen Arms) and have struggled helping him develop a good load. I tried talking him to a 7 MAG, but he had to go with the latest and greatest😳

Equipment - A&D scale, Wilson Bullet Seater, (borrowed some Lee Dies - Redding dies on order)
100 rounds down the tube so far
COAL: 2.940
Brass: Nosler (blems)
Bullet: Hornady 143 ELDX
Primer: FED 215M (also tried WIN LRP - no difference)
Powder: H1000 (55.0 to 57.0) no exceptional groups, developed pressure very early (~2880 FPS)
Powder: IMR8133 (56.0 to 57.5) .75/1.0 MOA, but FPS ~2800 range, loaded hotter but developed heavy bolt lift
Powder: IMR4831(47.5 to 49.5) at 49.0 shot 1/2" MOA ( AVG FPS @ 2841). Starting to develop heavy bolt lift

Side note - I shot 3 rounds of factory ammo (.7 MOA) and shot 1 round for velocity (3010 FPS). Hornady Precision Hunter 143 ELDX. I thought I could get close to duplicating this, but so far it's a no go. I'm sure I'm not the first to disassemble a factory load and find there is 54.84 to 54.86 of some type of powder, but it is definitely a mixture of powders. (Black powder with sprinkles of brown kernels, approx. 1 grain = .02)

Opinions/suggestions Welcomed😀. Should I just tell my friend to shoot factory ammo? He said he can't find any! I said there's plenty of it for sale on Gunbroker👍
 
Run the h1000 and play with seating depth.

I found one of my PRC really prefers the Berger 156, but it's a steel barrel. Sometimes Christensen barrels seem to like to be on the lighter end. Try 140 Berger or 135 ATips.
 
I'd try a different bullet, my 6.5x284 does not like the 143 ELDX, best I can get is about .75moa, burger 140 hybrids shoot .25 MOA. In my case I believe it's the longer bearing surface as I can't keep the pressure ring out of the should neck junction with the 143's. For speed go with RL 26.
The problem is your chambering. The rear part of the chamber cut is .002 too small. Go check out long range only they have a good article on it regarding cases sticking. Also order a JGS AW2 reamer and it will fix the problem. I had some Hand loaded 135 ATips with all kinds of pressure issues with a new CA barrel and I honed the back of the chamber out and can now run them at 3080 with no pressure issues using H1000. I could not reproduce the same velocity as factory Hornady 147's (3000fps) with any loads until I fixed the rear of the chambering issue
 
Run the h1000 and play with seating depth.

I found one of my PRC really prefers the Berger 156, but it's a steel barrel. Sometimes Christensen barrels seem to like to be on the lighter end. Try 140 Berger or 135 ATips.
Christensen Arms = No seating depth😀
I did start with 156 EOL's, however, to "meet" the short seating depth required on a CA, the 156's seemed close to a compressed load.
 
Can't go longer, Christensen Arms doesn't leave any room to push the bullet out further. I was jamming the lands at 2.960, that's when I was really seeing pressure😩

I've tested the difference of LRP versus Mag Primers on this rifle as well as my two 7 mags.........No POI change, No FPS change (3 rifles doesn't make it conclusive, but I always try it)

If it was me, I would start working on a seating depth test at the minimum powder charge. I would run the Berger seating test and find which COAL the barrel likes, then run the powder testing. Or, if you had any of the factory ammo left over measure COAL and seat at that length and run through the powder charges.

Going longer can make your pressure condition worse. I would agree with Kmccord and do a seating depth test.
It's good info for us that you tried the variation in primers.
 
I have NOT tried anything other than the Hornady 143's for two reasons.
1) Factory ammo is impossible to find and expensive
2) We have slowly accumulated brass, powders, primers and bullets

The rifle shoots well and I don't want folks to think I'm chasing FPS, but what I've read here on LRH...........2900 to 3100 FPS is a reasonable expectation.
Opinions/suggestions Welcomed😀. Should I just tell my friend to shoot factory ammo? He said he can't find any! I said there's plenty of it for sale on Gunbroker👍

Sure. I was just going by the last line in your OP - possibly misunderstood your post.
My son's rifle's factory group-test was done with the 147's so he just went with that for the first hunting season. Since Christensens should be throated the same, figured it might be worth a try for your friends rifle. I've run into that before. A slightly different weight can sometimes settle things right down.
Right now my son is working at developing some other options. 156 EOL and the 125 BD-2's... Anxious to see how that works out.
 
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