Why does MY 300PRC hate H1000?

[ruby76]

That's probably pretty close to my 26" barrel, ADG brass and 77.5gr H1000 pressure wise then.

I ran mine up to 78.9 and didn't have any typical pressure signs, using ADG brass as well. I did notice a jump in recoil at 78.3 so I dropped a bit. Don't have many rounds through my new build so will play around some more

 

[slikmrc]

I've found H1000 to be very consistent and repeatable in the two cases I run it in. It appears that your rifle will shot the bullet, I would do an OCW around your 77.5 load and look for POI shift as well as scatter nodes. I may have missed it but have you been seeing a POI shift between the powders at same velocity?

 

[Monteria]

I was able to do a very quick test today. I still have no mandrels, so I just took the expander ball out of my Forseter sizing die and went with what ever neck tension that produced. I didn't even measure it. I figured that even at the extreme, the test would at least tell me if increased tension would positively affect the ignition consistency.

Again, same everything except what ever extreme tension the die produced sans expander ball.

77.5gr of H1000 under a 225ELDM at 3.57"OAL

Previously 1.5" went down to 0.7".

Now here is the kicker. I forgot my rear bag and shot off a rolled up jacket. It was no where near steady. The 0.7" is pure horizontal and I'm certain due to crappy rear rest. It's got under .3" of vertical in it.

3 shots is hardly statistically relevant, but it's encouraging enough to pursue farther.

 

[Calvin45]

I was able to do a very quick test today. I still have no mandrels, so I just took the expander ball out of my Forseter sizing die and went with what ever neck tension that produced. I didn't even measure it. I figured that even at the extreme, the test would at least tell me if increased tension would positively affect the ignition consistency.

Again, same everything except what ever extreme tension the die produced sans expander ball.

77.5gr of H1000 under a 225ELDM at 3.57"OAL

Previously 1.5" went down to 0.7".

Now here is the kicker. I forgot my rear bag and shot off a rolled up jacket. It was no where near steady. The 0.7" is pure horizontal and I'm certain due to crappy rear rest. It's got under .3" of vertical in it.

3 shots is hardly statistically relevant, but it's encouraging enough to pursue farther.

Good test.

Now, just to be devils advocate…

Did you do the same tension test with 7828

Cuz you know it's gonna do even better AND DRIVE YOU NUTS!

 

[Monteria]

Good test.

Now, just to be devils advocate…

Did you do the same tension test with 7828

Cuz you know it's gonna do even better AND DRIVE YOU NUTS!

LOL, I had exactly that thought and I'm not doing it for that reason.

There is no longer purpose for a control, so I don't even have to talk myself out of it.

 

[Petey308]

I was able to do a very quick test today. I still have no mandrels, so I just took the expander ball out of my Forseter sizing die and went with what ever neck tension that produced. I didn't even measure it. I figured that even at the extreme, the test would at least tell me if increased tension would positively affect the ignition consistency.

Again, same everything except what ever extreme tension the die produced sans expander ball.

77.5gr of H1000 under a 225ELDM at 3.57"OAL

Previously 1.5" went down to 0.7".

Now here is the kicker. I forgot my rear bag and shot off a rolled up jacket. It was no where near steady. The 0.7" is pure horizontal and I'm certain due to crappy rear rest. It's got under .3" of vertical in it.

3 shots is hardly statistically relevant, but it's encouraging enough to pursue farther.

I'm curious what the difference ended up being on your muzzle velocity.

Either way, I'm glad to hear you're getting better results and that it looks like you can't blame the powder after all .

You've probably got around .006" of tension without an expander or mandrel to open the necks back up.

One think extra tension does is make up for uneven contact with the bullet. By increasing the amount, it makes up for uneven thickness of the brass and/or the engendered hardness and thus uneven spring back.

Proper annealing (keyword being proper), and using a mandrel to iron out the inside surface of the necks can really help you get the same result with less tension overall. Just good for thought. I know it sounds like that's the direction you're headed.

Good luck with continued success with it!

 

[Monteria]

I'm curious what the difference ended up being on your muzzle velocity.

Either way, I'm glad to hear you're getting better results and that it looks like you can't blame the powder after all .

You've probably got around .006" of tension without an expander or mandrel to open the necks back up.

One think extra tension does is make up for uneven contact with the bullet. By increasing the amount, it makes up for uneven thickness of the brass and/or the engendered hardness and thus uneven spring back.

Proper annealing (keyword being proper), and using a mandrel to iron out the inside surface of the necks can really help you get the same result with less tension overall. Just good for thought. I know it sounds like that's the direction you're headed.

Good luck with continued success with it!

I just measured and ended up with .005" tension. Previous was .002".

I didn't shoot any velocity rounds today (magnitospeed...)

That is the direction I'm headed. I just need time to get there.

Next test will be a 3 shot confirmation, and then a 5 round ladder in half grain increments, at longer range, to see where I pressure out and if I see any clustering.

Then who knows. But it's headed the right direction...

 

[Monteria]

I ordered a die body and .304 mandrel. I didn't want to spend $200 for a full set, and .005 tension worked well, so I'll start here and see what spring back lands me at.

 

[Monteria]

@haisardao , I renewed my membership at Dietz. I still refuse to shoot there during public access, but I get a guest (I think). Let's go shoot.

 

[haisardao]

@haisardao , I renewed my membership at Dietz. I still refuse to shoot there during public access, but I get a guest (I think). Let's go shoot.

Sounds like a plan! Thanks

 

[VarmintBob]

Your rifle has no emotions. It does not like, love or hate anything. If you need any help with load development, let me know. My last load development for 200gr ELD-X in 300 WM took about 15 shots. Here are the last 5 sighting shots.