300 PRC load development help

[m1ajunkie]

I recently picked up a Ruger precision rifle in 300 PRC I'm hoping to stretch out to 1000-2000 yds. At this point however I'm getting a little bit frustrated as I'm having trouble getting my load figured out. Looking for help on what I might be missing so I can get my velocity ES & SD performance where it needs to be for ELR. Would you read through the info below and provide some guidance?

Hornady brass
Federal 215M primers
230gr berger hybrid- .025" jump
Neck tension- .0015-.002
H1000 powder- I chose this as I want something very temp stable

During my initial ladder test with my magneto speed I saw the following results:

77.0 2815
77.2 2831
77.4- did not read
77.6 2834
77.8 2846
78.0 2859
78.2 2876
78.4 2863
78.6 2899
78.8 2892
79.0 2898

These 11 rounds shot into a group at 100 yds right 1"

Given my ladder test results I felt like the node was in the 78.8 range so I loaded up 10 more rounds and returned to the range for 2 5 shot groups over the magneto speed

Group 1
2870- average
17- sd

Group 2- fired almost immediately after the first

2887 average
15 sd

The results on my 2 follow up 5 round groups were very disappointing based on what I saw in my initial ladder test. My questions:

1. Is 78.8 the node I should be targeting?

2. Where should I be looking to improve my ES & SD?

3. Given the temp stability of the H1000 why am I seeing the velocity variation from my ladder testing with 78.8 grs to my first 5 rd group, and again when I fired my second 5 rd group?


Any help is greatly appreciated as I'm at a bit of a loss at the moment.

 

[Rocketmandb]

Was this virgin brass, or had it been fired before?

 

[m1ajunkie]

Was this virgin brass, or had it been fired before?

This was 1x fired hornady brass. Full length sized and I bumped the shoulders .002" .

 

[Rocketmandb]

Your ES/SDs are really excessive. By comparison, I went through the same process with a friend's new 300 PRC. We loaded rounds at the range after shooting the ladder in 15 mph winds with a portable scale and got SDs of 5 across 10 rounds.

With the numbers you're getting, I'm betting there's something else going on.

What are you using for sizing and seating dies? Bushing or non? Expander ball?

Have you measured concentricity?

How many rounds down the barrel?

 

[m1ajunkie]

Your ES/SDs are really excessive. By comparison, I went through the same process with a friend's new 300 PRC. We loaded rounds at the range after shooting the ladder in 15 mph winds with a portable scale and got SDs of 5 across 10 rounds.

With the numbers you're getting, I'm betting there's something else going on.

What are you using for sizing and seating dies? Bushing or non? Expander ball?

Have you measured concentricity?

How many rounds down the barrel?

Yes the ES and SD are ridiculous.... my 6.5CM I'm able to pretty easily get single digit SDs. It is worth noting the hornady factory 225 ELD load performs just as bad.

For the 300PRC I'm using hornady match grade dies, seating and bushing full length sizing die with the expander ball installed. I have been using the .334 bushing but I'm thinking I might move to a .333 to get a smidge more neck tension.

I have not measured concentricity but if needed I could figure out how to do that.

150 rds down the barrel. 100 factory and the rest are me working on load development with less than stellar results.

I'm really at a loss on this one.

 

[mbeavers1]

A couple thoughts:

1. Did you anneal and if so, how (flame or induction)?
2. Consider an expander mandrel instead of the expander button.

I have a few sets of the Hornady Match Grade dies (not 300 PRC) and have never gotten consistent neck tension with them so I removed expander and started using a turning mandrel and used a bit of dry neck lube. I can feel the bullets are seating more consistently. Previously, sesting depth rarely came out the same round-to-round and the amount of pressure I applied to the ram even felt different. New process and each round is very close on seatimg depth and the force feels very similar. I realize that is not completely scientific but it works very well for my 6CM for competition.

I am heading out to run a ladder with my 6.5x284 that was sized on usimg the match grades. Granted I just got my Amp, so this is my first run on this brass being annealed. I havent messed with this rifle since I started annealing cuz I've been too tied up w my 6CM. I am definitely interested to see if things tighten up.

 

[m1ajunkie]

A couple thoughts:

1. Did you anneal and if so, how (flame or induction)?
2. Consider an expander mandrel instead of the expander button.

I have a few sets of the Hornady Match Grade dies (not 300 PRC) and have never gotten consistent neck tension with them so I removed expander and started using a turning mandrel and used a bit of dry neck lube. I can feel the bullets are seating more consistently. Previously, sesting depth rarely came out the same round-to-round and the amount of pressure I applied to the ram even felt different. New process and each round is very close on seatimg depth and the force feels very similar. I realize that is not completely scientific but it works very well for my 6CM for competition.

I am heading out to run a ladder with my 6.5x284 that was sized on usimg the match grades. Granted I just got my Amp, so this is my first run on this brass being annealed. I havent messed with this rifle since I started annealing cuz I've been too tied up w my 6CM. I am definitely interested to see if things tighten up.

I am not annealing at this point and for my 6.5cm stuff I never have. In the places where I've asked for help I'm getting a lot of comments around case neck prep and around the powder scale so these are both areas I'm looking to address prior to continuing load development.

 

[918v]

Your high SD means your powder charge is wrong.

 

[Rocketmandb]

Your high SD means your powder charge is wrong.

Not necessarily. Inconsistent neck tension and out of whack concentricity could cause high ES/SDs too.

 

[918v]

The OP listed consistent neck tension.

 

[b2lee]

What chronograph was being used?

 

[Rocketmandb]

The OP listed consistent neck tension.

Yeah, but unless you're neck turning or using a mandrel, that may be the measured neck tension, but it certainly isn't the actual when using Hornady brass.

 

[918v]

Hornady brass is made well enough to produce low ES. I have no problem getting single digit SD with my 300WM brass.

 

[Rocketmandb]

Hornady brass is made well enough to produce low ES. I have no problem getting single digit SD with my 300WM brass.

It can be, but you need to prep it correctly. Neck thickness and case volume both vary fairly significantly in the 300 PRC cases I have measured. I started fire forming 8x68S into 300 PRC because I was getting mediocre results with Hornady and the cases didn't last long enough for my taste. I no longer do that because ADG now has 300 PRC brass - and I get similar numbers in the 5-6 range.

 

[Steel head]

It can be, but you need to prep it correctly. Neck thickness and case volume both vary fairly significantly in the 300 PRC cases I have measured. I started fire forming 8x68S into 300 PRC because I was getting mediocre results with Hornady and the cases didn't last long enough for my taste. I no longer do that because ADG now has 300 PRC brass - and I get similar numbers in the 5-6 range.

I met a guy Friday with a 300 PRC
He tested water capacity on his Hornandy brass and said it was quite bad compared to his new ADG brass

 

[Rocketmandb]

I met a guy Friday with a 300 PRC
He tested water capacity on his Hornandy brass and said it was quite bad compared to his new ADG brass

I'm quite happy with ADG. Do you use their SAUM brass?

 

[Steel head]

I'm quite happy with ADG. Do you use their SAUM brass?

 

[Rocketmandb]

View attachment 7346059

Oh yeah - I forgot the other great thing about ADG: Free orange ammo boxes

 

[Steel head]

Oh yeah - I forgot the other great thing about ADG: Free orange ammo boxes

I’m on my 14th loading and primer pockets are still perfect.
It awesome brass.

 

[AXMC338L]

Did a similar ladder test with ADG brass, H1k, 230 hybrids and 220 ELDX. I settled on 77.5g for both and shot this 10+ rd group with both bullets. Sorry the pic is rotated 90deg left

if this isn’t repeatable on 1x brass I’m getting a different sizing die. I’m guessing die and brass could both be the issue.

 

[sms0131]

Deviant action, 26” proof carbon sendero 1:10, piercision 5 port brake, ADG brass, H1000, 225 ELDM, CCI 250, 20 thou off the lands. Used 21ST century 0.307 expander. Redding dies

less than 30 rounds through the rifle. Loaded up quick ladder test.

had a node around 2815 with ES of about 19fps spreading over 0.8gr (.2 increments). Had a second node around 2865 about 25fps ES spreading over another 0.8gr (.2 increments

next time out, I’m gonna load some 5 shot groups somewhere in both those nodes to find the best.

btw, factory Hornady 212 shot a 0.29MOA GROUP but the ES and SD were terrible with factory rounds

 

[m1ajunkie]

Appreciate all the comments. For reference I'm using a magneto speed chronograph which has worked really well on all my other rifles. The neck tension I provided is what I measured with hornady brass.

At this point I have decided I'm going to order some ADG brass to work with as well as a better powder dispenser/ scale setup and I'm going to start over with load development.

 

[b6graham]

get rid of the expander ball and get a mandrel

then reattempt

 

[Dthomas3523]

Not sure all the tools you’re using, but here is a list of things that will easily get your es down:

Scale capable of one kernel
Using mandrel to set neck tension
Using a pin gauge to verify your actual neck tension

Once ES is down, then you can focus on the bullet.

 

[m1ajunkie]

Based on the feedback I've received I've ordered several items to improve my reloading process. 2 key items are I purchased virgin ADG brass and a sinclair carbide expander mandrel setup. From there I plan to start back at square 1 with my load development using my new practices.

That said I'm looking for thoughts on the following:

- I'll have to use virgin ADG brass for ladder testing and load development. Is this okay? How should I prep the virgin brass? Run through my bushing FL size die and then the mandrel or just run the mandrel through them and call it good?

- Now that I've moved to the mandrel for neck tension how do I select the proper neck size bushing to run in my die?

Thanks

 

[Dthomas3523]

How many rounds on the barrel?

 

[sms0131]

I started using a mandrel for first time with this new PRC, so I may not be the most experienced. However, this is what I’ve done. With my ADG brass, my loaded diameter of neck was .337, so I bought a .334 bushing for my Redding die. This should squeeze down to .003 tension but 0.002 tension after springback. And then I will use my 0.307 expander (.001 under diameter) to again give .002 tension after expansion. Running over the expander should give more consisting inner diameter tension with better uniformity. However, with virgin brass I haven’t run through the sizer die because they’re virgin and didn’t need to be squeezed down to size. I just skipped right to the expander mandrel, chamfered and deburred.
I’ve had decent luck so far running Satterlee test, then running a few groups in the node to verify. So far I’ve found a node that gave me ES of 15 SD of 7 and a 0.9” group at 300 yards.

Based on the feedback I've received I've ordered several items to improve my reloading process. 2 key items are I purchased virgin ADG brass and a sinclair carbide expander mandrel setup. From there I plan to start back at square 1 with my load development using my new practices.

That said I'm looking for thoughts on the following:

- I'll have to use virgin ADG brass for ladder testing and load development. Is this okay? How should I prep the virgin brass? Run through my bushing FL size die and then the mandrel or just run the mandrel through them and call it good?

- Now that I've moved to the mandrel for neck tension how do I select the proper neck size bushing to run in my die?

Thanks

 

[m1ajunkie]

Dthomas3523- 160 rounds down the barrel

sms0131- your results are exactly what I'm after. If I could get that kind of performance I'd be happy and move from load development to shooting steel. I've been running the .334 bushing so I'll use that with my ADG brass and since it's virgin just go straight to the mandrel.

Once again appreciate all the help.

 

[m1ajunkie]

So I picked up some virgin ADG brass, a carbide mandrel .002" below bullet diameter, and a sinclair LE Wilson bullet seater die in a K&M arbor press. Tonight I loaded up my first rounds using my new components and processes and ran them through my hornady concentricy tool.

What is the goal for bullet concentricity?

When running my rounds through the tool after after coming out of the seater I was seeing concentricity between .001-.003". Just not sure what is considered normal. Should I use to the hornady concentricity tool to try and reduce the runout I'm seeing?

 

[TripleBull]

What is the goal for bullet concentricity?

In the fantasy world, it's zero, zip, nada.

By "bullet concentricity", do you mean out near the meplat? I measure the brass at the neck and the bullet ~3mm from the tip of the meplat. If you look at factory, the results are fairly depressing. For example, some people talk as if Lapua is high quality. I bought 200 rounds of Lapua 338LM with 300 grain Scenar. Neck concentricity averaged just over 2 thousandths with an SD of 0.8 thousandths. After firing then sizing the neck with a Redding bushing die, and then running a mandrel, the neck concentricity dropped to 0.6 thousandths with an SD of about 0.3 thousandths.

Out near the meplat, the factory ammo ran 7.7 thousandths with an SD of 3.2 thousandths. Ouch. Handloading can cut those in half or better. But if nerd this out to the max, you probably want to measure consistency of neck thickness and before you know it, you'll be turning necks. It's a vicious cycle that could lead you over to the dark side where you read and worship benchrest fanatics and buy an apparatus that helps you to put both legs of your pants on at the same time.

For my 300 PRC, I started with virgin ADG brass, cleaned up the mouth and ran a .3055 mandrel and was ready to go. See post #14 on this thread:

300 PRC

I decided to mine the 300 PRC thread in the ELR subforum for handload data ahead of starting to work up a load for my rifle, working backwards from recent posts. I think I fully mined that thread as of today (11/27/19) but if I missed any please plug them in or post your own load data. I know...

www.snipershide.com

 

[m1ajunkie]

So I've set my concentricity gauge to measure at the ogive on the bullet. When I made my post above about seeing a run out of .001-.003" I was loading in virgin ADG brass that I had run the mandrel through. This afternoon I loaded into 1x fired ADG brass and ended up seeing run out of all my bullets in the .001" range.

Very excited to hit the range tomorrow!

 

[jeepguy88]

What's the update? I'm curious what numbers your getting with the different brass. I'm also having trouble getting consistent velocity with my 300prc

 

[m1ajunkie]

What's the update? I'm curious what numbers your getting with the different brass. I'm also having trouble getting consistent velocity with my 300prc

Given work and the heat out here at the moment I don't really have an update yet as I haven't been shooting. At this point I still haven't got velocity where I want to be but I haven't worked on it either.

 

[jeepguy88]

Thanks for the update. I was hoping you found the magic answer.
Good luck.

 

[m1ajunkie]

Thanks for the update. I was hoping you found the magic answer.
Good luck.

Now that I've picked up all these new reloading tools I'm actually planning to start over with another ladder test and see what that shows.

 

[ABC1000]

Any updates on your results yet? I’m not neck turning just FL sizing w my new 300 PRC and 10 shots in am getting over 2,900 FPS w no pressure signs or marks on brass other than the slight ejector mark I had all the way through the 10 round test (75-79.5 grains of retumbo, 215m and 225 ELD-ms and new ADG brass).
I am running a 26” shouldered carbon proof sendero but didn’t expect as much velocity.
i waited for the Forster FL sizing dies to come out so am just getting started on the 300 PRC project.
First ten shots (81 degrees and 5k elevation w a 5MPH 6:00 wind results are:
1-75.0 test fire
2-76 2,757 FPS
3-77 2,839 FPS
4-77.5 2,821 FPS
5-78.0 2,865 FPS
6-78.3 2,879 FPS
7-78.6 2,886 FPS
8-78.9 2,908 FPS
9-79.2 2,921 FPS
10-79.5 2,909 FPS

have any of you shot the 225 eld matches yet? I also picked up a box or two of the 212 eld-Xs in case the 225s couldn’t get enough velocity.

 

[b2lee]

@ABC1000 I started off with the 225 ELD-M's....if you go WAY back through this thread I should have plenty of data with various powders...including Retumbo.

Tomorrow I'll be shooting 250 A-Tips...but I'm not too optimistic with my accuracy at 2400yds with over 1200 rounds through this barrel. My velocity on a 75F day was about 2905fp/s on a 28" bartlein....Tomorrow should have shooting conditions at about 63F for the HIGH of the day. Probably dip down just enough in velocity to where I'll have to hold a mil in the reticle. We will see what tomorrow brings. Should be a good match at TVP with some good shooters and good friends.

 

[ABC1000]

@ABC1000 I started off with the 225 ELD-M's....if you go WAY back through this thread I should have plenty of data with various powders...including Retumbo.

Tomorrow I'll be shooting 250 A-Tips...but I'm not too optimistic with my accuracy at 2400yds with over 1200 rounds through this barrel. My velocity on a 75F day was about 2905fp/s on a 28" bartlein....Tomorrow should have shooting conditions at about 63F for the HIGH of the day. Probably dip down just enough in velocity to where I'll have to hold a mil in the reticle. We will see what tomorrow brings. Should be a good match at TVP with some good shooters and good friends.

thanks for the help. I’ve not a few boxes of the a-tips in 338 (300 gr) but haven’t shot them yet in my 338 LM but need to. I’d be interested in the 250s in PRC as well. I’ll check out your previous posts. Thanks again.

 

[b2lee]

yea..I don't know exactly what thread I posted the MagnetoSpeedV3 speeds of the 225's in....so you may have to dig through a few of them.

 

[jeepguy88]

Im running 225ELDM's.
Hornady brass
78.1gr Ramshot Magnum
CCI 250 primers
AVE 2873
26" barrel 1:8 twist.

The 225ELDM shot just a lil better at 600yards than the 212ELDX with a lil more consistant velocities for me. Ran out of 212's before I could get a chance to shoot at distance. Im going to stay with the 225's

This is my 3round group at 1mile with the 225ELDM

 

[ABC1000]

yea..I don't know exactly what thread I posted the MagnetoSpeedV3 speeds of the 225's in....so you may have to dig through a few of them.

I found the data! That helps a ton! Thanks again

 

[ABC1000]

Im running 225ELDM's.
Hornady brass
78.1gr Ramshot Magnum
CCI 250 primers
AVE 2873
26" barrel 1:8 twist.

The 225ELDM shot just a lil better at 600yards than the 212ELDX with a lil more consistant velocities for me. Ran out of 212's before I could get a chance to shoot at distance. Im going to stay with the 225's

This is my 3round group at 1mile with the 225ELDM
View attachment 7426937

I bought a couple boxes of 225s and will establish those as well. I’ve seen a couple guys shoot that ram shot but haven’t never tried it myself. Thanks for the help.. seems like a lot of guys like that 2840-2,900 FPS.

 

[jmm68]

@m1ajunkie I bought the very same rifle and still waiting for some official load data, here in Switzerland we don't have easy access to american powders and I'm going to use N565. Any progress with your Ruger PRS 300 PRC? How is it shooting?
BR from switzerland. I have some ADG brass and 230 Atips but my idea is to run the barrel break with some cheaper 175 gn Nosler competiton.

 

[m1ajunkie]

@m1ajunkie I bought the very same rifle and still waiting for some official load data, here in Switzerland we don't have easy access to american powders and I'm going to use N565. Any progress with your Ruger PRS 300 PRC? How is it shooting?
BR from switzerland. I have some ADG brass and 230 Atips but my idea is to run the barrel break with some cheaper 175 gn Nosler competiton.

I still haven't achieved velocities that I'm really excited about but I've ended up with a load that I'm happy enough with..... I'm tired of shooting paper at 100 and I'm ready to stretch out and shoot some steel for a change.

Went out this morning with:
230 berger hybrids
77.8 gr H1000

Velocity averaged 2861, with an ES of 25 and an SD of 9.5. Not great but noticeably better than I've been seeing and it's shooting well. Hoping to stretch out to 1000+ maybe tomorrow.

The low rd was my cold bore: