300 PRC update

[b2lee]

I went to the range today to get the 308 ready for hunting season...and while I was there I decided to shoot some of my load developments for the 300PRC.

I decided to just do a 6 shot test looking for an accuracy node. I used the 225gr ELD-M's instead of the 230gr A-Tips because I have a few hundred ELD-M's that I'm not really going to use...but I can use them in these kinds of tests. I did NOT remember to take the chronograph since I more interested in simply getting the scope on the hunting rifle dialed in at 100yds and as a last minute thing decided to take the 300PRC for the load work up.

So, I did take a few retailed 225gr ELD-M's to see how much different in impact height it was from these work up loads...and to re-affirm Zero. First shot was within half a bullet of zero vertically..so it was good to go...wind was about 20mph right to left.

So fresh target....I shot in order of 75gr, 76gr, 77gr, 78gr, 79gr and 80 grains of Vihtavuori N565. My previous accuracy node using Retumbo on these 225gr ELD-M's was 75.5gr. As you will see...N565 and Retumbo...atleast in my rifle...acted very close to each other.

Looks like the VihtaVuori N565 is ready to play. That accuracy node at 75-77 grains looks really sweet. Probably load some up at 76 grains and work on some seating depths.......but I should be good to go with this load. Brass showed ZERO pressure signs. I'm wondering how far north of 80 grains I can go. Maybe another accuracy node up there with MORE speed...

One side note though.... The N565 was noticeably dirtier than ole Retumbo...which was surprising to me.

Edit: Bullet weight errors.

 

[kjnolder]

Not that anyone cares, but a Hornady case will hold 95.0 gr of RL 33. I will try an ADG case when they arrive.

Why does this matter? Cause a 6.5 creed Lapua case will hold exactly 50.0 gr of RL 26 and push a 156gr at 3000fps with that 50gr of powder with no pressure and single digit SD. If science can do that, then it can push a 250gr A tip at 3000 FPS out of a PRC. I don’t know what the ballistics are on that, but it changes things.

 

[goinghunting]

Not that anyone cares, but a Hornady case will hold 95.0 gr of RL 33. I will try an ADG case when they arrive.

Why does this matter? Cause a 6.5 creed Lapua case will hold exactly 50.0 gr of RL 26 and push a 156gr at 3000fps with that 50gr of powder with no pressure and single digit SD. If science can do that, then it can push a 250gr A tip at 3000 FPS out of a PRC. I don’t know what the ballistics are on that, but it changes things.

You're running the 156 3000 with no pressure in a 6.5 Creedmoor? Or 6.5 PRC?

 

[benchmstr]

You're running the 156 3000 with no pressure in a 6.5 Creedmoor? Or 6.5 PRC?

No shit, if thats the case im selling off my pieces for my current 6.5 PRC build

I know benchrest guys are hitting over 3000fps in a 6.5 creedmoor.....but that a single shot 30" barrel

bench

 

[b6graham]

Not that anyone cares, but a Hornady case will hold 95.0 gr of RL 33. I will try an ADG case when they arrive.

Why does this matter? Cause a 6.5 creed Lapua case will hold exactly 50.0 gr of RL 26 and push a 156gr at 3000fps with that 50gr of powder with no pressure and single digit SD. If science can do that, then it can push a 250gr A tip at 3000 FPS out of a PRC. I don’t know what the ballistics are on that, but it changes things.

This is bad advice

 

[vergil]

I have a 28 inch Krieger barrel and Origin action, I can get around 2900 with RL 16 using Hornady 147 Eld's before seeing pressure signs, 3000 with 156's impressive nonetheless would love to know your setup.

 

[DangerRanger]

 

[LakuNoc]

I think lots of guys get carried away with FPS and how hot they can push the load, getting 3000 or 3100 FPS and maxing out 300 PRC.
IF you want to go faster get bigger cartridge 338, 375,416 or some others.
I will take 300 PRC shooting 80.06gr of H1000 powder and 230 A-tip traveling at 2935FPS and be stable from -10 Fahrenheit temp to 100 Fahrenheit and be very stable at any temperature. FPS will change 35FPS at most from very cold to very hot with H1000.
Where powders like N565 and RL22,17 Retumbo will Fluctuate up to 140FPS from -10Fahrenheit to 100Fahrenheit for example at -10 will travel 2900FPS and at 100Fahrenheit will travel 3050FPS. Someone like me shooting at long distance i try to stay away from those powders and i take slower H1000 but very stable at any shooting conditions.
Just my own test i did and my opinion not trying to start argument with anyone.

 

[b6graham]

I think lots of guys get carried away with FPS and how hot they can push the load, getting 3000 or 3100 FPS and maxing out 300 PRC.
IF you want to go faster get bigger cartridge 338, 375,416 or some others.
I will take 300 PRC shooting 80.06gr of H1000 powder and 230 A-tip traveling at 2935FPS and be stable from -10 Fahrenheit temp to 100 Fahrenheit and be very stable at any temperature. FPS will change 35FPS at most from very cold to very hot with H1000.
Where powders like N565 and RL22,17 Retumbo will Fluctuate up to 140FPS from -10Fahrenheit to 100Fahrenheit for example at -10 will travel 2900FPS and at 100Fahrenheit will travel 3050FPS. Someone like me shooting at long distance i try to stay away from those powders and i take slower H1000 but very stable at any shooting conditions.
Just my own test i did and my opinion not trying to start argument with anyone.

Action size/options
Brass and powder cost

Powder cleanliness with cans especially
People who live in not such crazy climates

 

[kjnolder]

I have a 28 inch Krieger barrel and Origin action, I can get around 2900 with RL 16 using Hornady 147 Eld's before seeing pressure signs, 3000 with 156's impressive nonetheless would love to know your setup.

I am running a 24” proof with defiance action. Running the 156 Berger’s with 49.5gr of RL 26. 6.5 creedmoor with magnum small rifle primers. I agree with everyone, accuracy over velocity.

What I meant in my post is that I am amazed at the science of powder and how it will change cartridge development in the future. For three years I loaded my Creed with H4350 because that’s what you are suppose to use. Then someone told me to try RL 26 and it completely changed everything. I am throwing out the idea that RL33 may be the cats meow for 300 PRC with heavy for caliber bullets, much like RL 26 is for the creed. In three weeks I will try it out and let everyone know. I will go in 0.5 gr increments up to 95 gr.

 

[Merovingian]

I think lots of guys get carried away with FPS and how hot they can push the load, getting 3000 or 3100 FPS and maxing out 300 PRC.
IF you want to go faster get bigger cartridge 338, 375,416 or some others.
I will take 300 PRC shooting 80.06gr of H1000 powder and 230 A-tip traveling at 2935FPS and be stable from -10 Fahrenheit temp to 100 Fahrenheit and be very stable at any temperature. FPS will change 35FPS at most from very cold to very hot with H1000.
Where powders like N565 and RL22,17 Retumbo will Fluctuate up to 140FPS from -10Fahrenheit to 100Fahrenheit for example at -10 will travel 2900FPS and at 100Fahrenheit will travel 3050FPS. Someone like me shooting at long distance i try to stay away from those powders and i take slower H1000 but very stable at any shooting conditions.
Just my own test i did and my opinion not trying to start argument with anyone.

2nd all that. Too many times shooting with people that can't find consistency beyond 500 and find out they're focusing on FPS not accuracy. No point in pushing 3000+ if you can't get it go where you want it to. I'm in CO where it can be 30 degrees at 7am and 70 degrees at noon so temp stable powders are in my opinion the only way to go. Finally, I've rarely found an accuracy node at the upper edge that outperforms alternatives. KJ if you're thinking about trying to push a 250 at 3000 out of the PRC, I anticipate you'll be wasting your time and money if not putting your platform at risk. But in all sincerity, I'm curious to see what happens as long as you do it safely.

 

[TripleBull]

If you want more MV why not just buy a longer barrel? We're getting ~3000 out of factory ammo.

 

[b6graham]

If you want more MV why not just buy a longer barrel? We're getting ~3000 out of factory ammo.

hunting scenario

 

[Merovingian]

It will hold higher pressure, primer pockets don't get lose as fast as lapua brass, his RCC 338 brass primer pockets are still good after 19 firings.
Also brass is more concentric internal volume measures exactly same within .05 measuring with H2O.
but as i said in earlier post i will be getting RCC brass for 300 PRC this coming up week and will do full test and review on RCC brass.
Also yes i paid for my brass with my $$$ which cost me around $600 for 100 pieces.
Will do review and will see if it will be worth.

What did you order your neck thickness at? Reason I ask is I'm having trouble keeping 230 BHT's below .75 but this happened after I turned the necks down to .014 (neck variance <.0005, neck runout <.001, concentricity <.001, ES 24). Thinking I maybe should have accepted the .003 variance but kept the lot closer to .016 / .340 OD. Oddly enough the 200 SMK's aren't exhibiting the same variance holding easily <.5 with a higher ES.

 

[LakuNoc]

My neck thickness will be at .014 i will be using 230 A-Tip. Will tell you what happens later this week i will begin testing. Try different neck bushing put more pressure on it or try bumping powder up untill you reach max pressure. I find my node always right under max pressure. But again be careful, H1000 max is right about 80.6gr with 230 A tip and hornady brass and ES was under 10FPS. I’m at 1100 feet 40 F temp.

 

[Dooby]

Originally RCC had my spec at 0.017" neck thickness. But brought down to 0.014". I don't plan to neck turn

 

[Merovingian]

Originally RCC had my spec at 0.017" neck thickness. But brought down to 0.014". I don't plan to neck turn

17 would have been right at 342? Odd that they would want to run it that tight. I think you made the right decision.

 

[Merovingian]

My neck thickness will be at .014 i will be using 230 A-Tip. Will tell you what happens later this week i will begin testing. Try different neck bushing put more pressure on it or try bumping powder up untill you reach max pressure. I find my node always right under max pressure. But again be careful, H1000 max is right about 80.6gr with 230 A tip and hornady brass and ES was under 10FPS. I’m at 1100 feet 40 F temp.

Thanks for the suggestion. Apparently wasn't out in left field turning to 14. May just still fighting the crappy Hndy brass. H1K peaked for me at 77.9/2890, backed it down to 77.6/2870 (27" 1:9 Suppressed). There's a CBTO change there too because shorter OAL's were running better. I've got 10 now at 77.3 that I'm pushing back up to .020 & .030 off to see what happens. Also rolled up a 215 BHT ladder. If I can't get 230's to calm down, and the 215's are too slow to make up the difference, I may have to join you at $0.90 a pop.

 

[LakuNoc]

Thanks for the suggestion. Apparently wasn't out in left field turning to 14. May just still fighting the crappy Hndy brass. H1K peaked for me at 77.9/2890, backed it down to 77.6/2870 (27" 1:9 Suppressed). There's a CBTO change there too because shorter OAL's were running better. I've got 10 now at 77.3 that I'm pushing back up to .020 & .030 off to see what happens. Also rolled up a 215 BHT ladder. If I can't get 230's to calm down, and the 215's are too slow to make up the difference, I may have to join you at $0.90 a pop.

I think reason i can push 230 A-Tips faster and go up to 80.6 gr with H1000 untill i hit maximum pressure is because i coat them with Hex boron Nitride (hBN).

 

[dukerugger25]

Got the 300PRC to the range finally for ladder testing. Used 225gr ELDM'S, RL-26 and 215m primers. Barrel is 26" and 9.5tw.

Found two nodes: 74.1gr - 2856fps, 76.0gr - 2937fps. Slight ejector swipe at 77gr (2974fps), primers were still round and no noticeable increase in bolt lift. Stopped there. I will load up some for seating at both nodes and test accuracy in a few weeks. Still have a late season archery tag to fill.

Factory 225 loads were shooting at 2880fps for comparison.

 

[Rocketmandb]

Got the 300PRC to the range finally for ladder testing. Used 225gr ELDM'S, RL-26 and 215m primers. Barrel is 26" and 9.5tw.

Found two nodes: 74.1gr - 2856fps, 76.0gr - 2937fps. Slight ejector swipe at 77gr (2974fps), primers were still round and no noticeable increase in bolt lift. Stopped there. I will load up some for seating at both nodes and test accuracy in a few weeks. Still have a late season archery tag to fill.

Factory 225 loads were shooting at 2880fps for comparison.

What contour and manufacturer on the barrel?

 

[dukerugger25]

Hells Canyon armory, it's a carbon fiber wrapped benchmark.

 

[waveslayer]

Got the 300PRC to the range finally for ladder testing. Used 225gr ELDM'S, RL-26 and 215m primers. Barrel is 26" and 9.5tw.

Found two nodes: 74.1gr - 2856fps, 76.0gr - 2937fps. Slight ejector swipe at 77gr (2974fps), primers were still round and no noticeable increase in bolt lift. Stopped there. I will load up some for seating at both nodes and test accuracy in a few weeks. Still have a late season archery tag to fill.

Factory 225 loads were shooting at 2880fps for comparison.

Where are you finding the RL 26 at, it is like a Unicorn...

 

[goinghunting]

Where are you finding the RL 26 at, it is like a Unicorn...

Last week Powder Valley had some, lasted a few hours. Bruno's Shooter Supply also.

 

[357Max]

Powder valley and Bruno's are out.

 

[pengilly]

If you want more MV why not just buy a longer barrel? We're getting ~3000 out of factory ammo.

Im getting 3000 FPS out of factory 225
The next thing i need to do is double check my chrony with another one
28" Bartlien 9:1. My 212 load is one ragged hole 3210 fps low SD I ran my load on QL with an H2O case capacity and it was just over SAAMI max @ 66,000 psi i can load it down but it shoots so good and im in a node.

 

[LakuNoc]

What Muzzle Brake are you guys running on your 300 PRC?
Thank you

 

[b2lee]

What Muzzle Brake are you guys running on your 300 PRC?
Thank you

APA Lil' B....makes it kick like an AR

 

[LakuNoc]

APA Lil' B....makes it kick like an AR

how heavy is your rifle?

 

[NVScout]

#BRAKESAREFORBITCHES HAHAH ! Mine is 10.2 loaded and after about 20 rnds you definitely start to feel it. Still plan on shooting her bare until the ultra 7 gets out of jail.

 

[b2lee]

how heavy is your rifle?

Heh....it's a nice slim trim 22lbs....without the scope.

 

[b2lee]

I wanted to post this little tidbit of information on my reloading. Yesterday I got around to reloading 21 pieces of brass I shot the other day on a load work up. 1 piece was a retail round, so this would be the first loading. I resized and trimmed to 2.565". I then resized the other 20 pieces and went to trim....and nothing. I mic'd and found that I had zero growth on these 5x fired brass. Primer pockets were still very snug as well.

Even the piece marked at 80gr of N565 had zero growth and the primer pocket had the same snug feel on seating a new Federal GMM #210. Originally I trimmed 50 pieces of new brass, loaded and shot....and on the first reload I had about 8-10 thou of growth....but nothing since then.

Also, after the next firing...I will most likely have to anneal them. However, they still seem to have consistent neck tension.

And another thing. Zero'd the rifle using 230gr A-Tips and Vihtavuori N565 on a 70F day. This morning it was 18F. My shots were within an error factor that could just be me and the cold. MV averaged with 20fps difference than the 70F day with and SD of 8.

 

[gnochi]

I wanted to post this little tidbit of information on my reloading. Yesterday I got around to reloading 21 pieces of brass I shot the other day on a load work up. 1 piece was a retail round, so this would be the first loading. I resized and trimmed to 2.565". I then resized the other 20 pieces and went to trim....and nothing. I mic'd and found that I had zero growth on these 5x fired brass. Primer pockets were still very snug as well.

Even the piece marked at 80gr of N565 had zero growth and the primer pocket had the same snug feel on seating a new Federal GMM #210. Originally I trimmed 50 pieces of new brass, loaded and shot....and on the first reload I had about 8-10 thou of growth....but nothing since then.

Also, after the next firing...I will most likely have to anneal them. However, they still seem to have consistent neck tension.

And another thing. Zero'd the rifle using 230gr A-Tips and Vihtavuori N565 on a 70F day. This morning it was 18F. My shots were within an error factor that could just be me and the cold. MV averaged with 20fps difference than the 70F day with and SD of 8.

Which brass did you end up using? Hornady? And that’s great to know about the N565.

 

[b2lee]

This test was on the Hornady Brass I got back before I even had my rifle. I will be getting RCC and ADG Brass....well...RCC Soon...and ADG when it is released.

On the difference in MV...Those numbers are less than the 0.5fps per degree F I was accustomed to getting with other stable powders.... does that 'jive' with other peoples beliefs/data on what they get with their stable powders?

Also, on the 70F day the ammo set out and became 'room temp' but not in the sun for about 30mins...under a covered shooting bench. On the 18F shooting....it was in the trunk of the car at about half an hour at maybe 60F...and then under the same covered bench at 18F fairly shielded from the wind...for a good 30mins before I got to shooting. I've always wanted to do a test of putting some rounds in dry ice and then shooting...and putting some in my food dehydrator I use to dry out my brass....and take a temp reading at about 130F before shooting...and measuring the MV difference.

 

[b2lee]

Another note.... N560 is not temp stable...and neither is N570....but N565 is and is marketed as very temp stable...which I have seen.

I do have a question that probably needs to be asked in a different thread...but what is the temp stability of something like a Magneto Speed V3? If more than I expect...how could I analyze the difference in MV and attribute it to powders/primers or to the measuring equipment.

But...if I am close enough in MV to actually have to ask that question...my load is probably good to go no mater what.

/end OCD Rabbit Hole

 

[gnochi]

Assuming the plastic that the magnetospeed sensors are mounted to is something along the lines of 30% glass filled Nylon 66 (I haven’t found pictures of mold markings on the part but that would be PA66GF30 if anyone has one disassembled):

• Coefficient of linear thermal expansion ~50 microns per meter Kelvin (0.005% per degC, a hair under 0.0028% per degF)
• 3000fps nominal
• -20 to 130F ammo temps

There may end up being some differential signal lag, etc., but mechanically the worst you can end up with for a time-vs-distance measurement is 0.084 FPS per degree and an extreme spread of measurements of 13fps across those ranges, compared to 75fps for the powder assuming your numbers hold.

This is also consistent and can be corrected for in the magnetospeed itself (if they bothered) and your dope (which you need regardless for powder trueing), so I think it’s fair to assume that temperature variance of the magnetospeed itself can be ignored.

 

[Dooby]

Just got tracking for my RCC brass

 

[goinghunting]

Just got tracking for my RCC brass

When was it ordered? Been contemplating some.

 

[LakuNoc]

I'M starting writing and doing review on RCC brass should have it all done by weekend.

 

[jasent]

I have measured h1000 at .21 fps per degree f
This was with a 338/375 ruger improved and 243 win and 338 lapua. Using a temp gun to check ammo temps and coolers both warm and cold. Jme

 

[benchmstr]

what kind of barrel life are you guys getting?

I am approaching 1000 with mine and figure thats where the life cycle will probably end.

bench

 

[pengilly]

what kind of barrel life are you guys getting?

I am approaching 1000 with mine and figure thats where the life cycle will probably end.

bench

Depends how hot you load it and how you treat that barrel when shooting

 

[benchmstr]

Depends how hot you load it and how you treat that barrel when shooting

Of course, but most calibers for the exception of an extreme load will show a roundabout average.

bench

 

[pengilly]

Of course, but most calibers for the exception of an extreme load will show a roundabout average.

bench

1200 -1500 is what I was told by a barrel manufacturer. That he told me a story of a test where a 338 Lapua achieved around 34-3500 round life by loading at 2400 fps. So your load and how you shoot have a huge effect on barrel life

 

[gnochi]

I think @DAVETOOLEY mentioned earlier in the thread he had seen several barrels go north of 1500?

I don’t expect I’ll get that with 198 Flatlines over N565 at 3150ish, but you never know!

 

[Dooby]

I think Dave Tooley also mentioned he's not running hot loads

 

[benchmstr]

Mine has eaten nothing but Hornady factory loads of 225eldm. I wasn't sure if I was going to like the caliber and didn't want to invest in any reloading equipment for the caliber...so i just went factory.

I will build my load with the new barrel though...

In all honesty, i just want to hit about 2900-2950 and retain the same accuracy, but more consistent velocity than the hornady.

bench

 

[LakuNoc]

I finally got my RCC brass chambers in 300 PRC. Just to be clear i payed for my brass around $600 for 100 pieces. I took random 10 pieces of brass and did measurements.
As i stated before i will perform full review of RCC brass this is part 1 and part 2 will be coming after i do all testing on range.
I used Mitutoyo ball style Micrometer, and results were amazing.
Neck thickness of brass was within in 0.0005, 0.0005, 0.001, 0.0005, 0.001, 0.001, 0.0005, 0.001. 0.0005, 0.001. Better than Lapua brass that i use in my 6.5CM.

After neck thickness i weighted 10 pieces of brass. Using Lab scale FX-120i.
Brass was very close in weight 288.46gr 288.44 288.35 287.43 288,41 288.33 287,89 288.46 287.95 288.40.

Then i filled brass with H2O to measure internal case capacity and to see how consistent it was be using same scale. I think this is very important at least to me because i shoot long distance. This has big impact on Extreme Spread internal volume of brass is something that can be more than 10-20 GN that i witness in my 338Lapua brass which is consider one of best out there in my opinion.
Results came out again very consistent and close to each other.
Internal case H2O capacity: 90.98 90.91 90.81 89.90 90.80 90.91 90,82 90.99 90.98 90.95
So far I'm liking the results its very good.

Last in this part1 but not least i did perform Concentricity of brass i don't like to do this until i load ammo and do Concentricity of loaded ammo. Results were okay i can't say they were perfect because i like all my rounds to be within one thousands of and inch. I can't judge this part yet i want to fire brass at least once and load full ammo than do Concentricity on loaded ammo.
But results were okay no to write out all Measurements . Concentricity was 6 cases within in one thousands of and inch and 4 causes were 2 to 2.5 thousands of an Inch runout.

Part 2 will be:
-Load development to see how low of and extreme spread and SD i can get using RCC brass, H1000, BR-2 primers and 230gr A-Tip
-How many firings primmer pocket will hold with 80gr of H1000
-Will load case to maximum to see what kind of pressure it will hold comparing to Hornady brass which now is maxed out at 80.6Gr of H1000.

This is my test I'm no expert but i love long distance/precision shooting and as i said i payed for all this stuff with my own $$$. Just want to give something back because i learned a lot on here about 300 PRC.

 

[Rocketmandb]

Part 2 will be:
-Load development to see how low of and extreme spread and SD i can get using RCC brass, H1000, BR-2 primers and 230gr A-Tip
-How many firings primmer pocket will hold with 80gr of H1000
-Will load case to maximum to see what kind of pressure it will hold comparing to Hornady brass which now is maxed out at 80.6Gr of H1000.

This is my test I'm no expert but i love long distance/precision shooting and as i said i payed for all this stuff with my own $$$. Just want to give something back because i learned a lot on here about 300 PRC.

I highly recommend starting with a much lower powder charge and working up. I think somewhere in this thread someone did an H20 measurement of Hornady brass, and I seem to remember it being a decent bit higher.

 

[MOUNTIC]

I had slight starting signs of pressure at 80gr of h1k with 215 bergers in hornady brass. For what it's worth.