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300 PRC
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For better or worse most of the info is in the ELR forum:
www.snipershide.com
300 PRC update
The 300 PRC, 30-375R, will be a cataloged item with SAMMI in the next two weeks. I don't know how long it will take them to add it to their website. Dave Manson has the specs and can make anyone a reamer.
www.snipershide.com
Honestly we should rename that thread and have it pinned…. Like why the hell hasn’t it? There are wildcats that are pinned…. And 300 PRC isn’t?! Someone hates this cartridge.For better or worse most of the info is in the ELR forum:
300 PRC update
The 300 PRC, 30-375R, will be a cataloged item with SAMMI in the next two weeks. I don't know how long it will take them to add it to their website. Dave Manson has the specs and can make anyone a reamer.
Inbound! Just posted in the other thread and I’ll be dropping in some of my data today.
Ok so here is what I am currently running:
30" Bartlein barrel 1:9 tw
Lapua brass
Large Mag CCI primers
20 thousandths off the lands
2 thousandths shoulder bump
I am running 2 general standard loads.
220 Berger LRHT
78gr H1000
Muzzle Velocity ~ 2940 ft/s
Measure BC ~ 0.39 (granted this is from only taking distance readings out to 200yr) over 5 measurements.
245 Berger LRHT
81gr N570
muzzle Velocity ~ 2950 ft/s (upwards of 2960+ in hotter temps)
Measure BC ~ 0.44 (again only taking it out to 200yr over 5 measurement distances)
I have ran RamShot and I am working up some loads with Retumbo as I can finally get a hold of it to play with but the above are my primary loads.
30" Bartlein barrel 1:9 tw
Lapua brass
Large Mag CCI primers
20 thousandths off the lands
2 thousandths shoulder bump
I am running 2 general standard loads.
220 Berger LRHT
78gr H1000
Muzzle Velocity ~ 2940 ft/s
Measure BC ~ 0.39 (granted this is from only taking distance readings out to 200yr) over 5 measurements.
245 Berger LRHT
81gr N570
muzzle Velocity ~ 2950 ft/s (upwards of 2960+ in hotter temps)
Measure BC ~ 0.44 (again only taking it out to 200yr over 5 measurement distances)
I have ran RamShot and I am working up some loads with Retumbo as I can finally get a hold of it to play with but the above are my primary loads.
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Just tossing some data on the pile.
Lapua 300prc brass
Hornady 212 eld-x
CCI 250
79gr N565
26" barrel (Barrel that came with ASXR when purchased)
Velocity: 2975
SD is a disappointing 12 over 5 shots. Was just a random load and about .030 jump. Just testing waters with N565. Have been using N570 with very good results.
The other two shots are in there. Just got lucky they went through the larger hole the first three made.
Lapua 300prc brass
Hornady 212 eld-x
CCI 250
79gr N565
26" barrel (Barrel that came with ASXR when purchased)
Velocity: 2975
SD is a disappointing 12 over 5 shots. Was just a random load and about .030 jump. Just testing waters with N565. Have been using N570 with very good results.
The other two shots are in there. Just got lucky they went through the larger hole the first three made.
Try N560. With 212s I found that it worked pretty damn well. N570 for the heaviers, 245 and 250s.
Yea, was running 230 A-Tips with N570. These 212 were on shelf and decided to see what happens.
This is not the PX. Post items for sale there and do not bump for 48 hours as that is the site rule.
strange stuff with my 300PRC. these loads with new lapua brass clocked in 90 fps slower that the (mostly) equivalent loads with Hornady once fired brass. i did nothing to the new brass. i figure lapua knows how to sell ready to load brass. the seating operation was a shitshow. waaaaaaay tooooooo much force required.
anyway, the 1" groups were acceptable to me but the velocity metrics are not. the lapua brass is 5% larger in volume. reddit hive suggested the volume increase was biggest contributor to velocity drop. i'm too inexperienced to have developed instinct. I've since hit all the remaining virgin brass with a mandrel and will load out a new batch bumping the charge to get the velocity up and hope for smooth seating forces.
bottom line, i need 100 for an upcoming ELR match and dont want to go back the 1.6" groups the hornady 1x brass delivered.
anyway, the 1" groups were acceptable to me but the velocity metrics are not. the lapua brass is 5% larger in volume. reddit hive suggested the volume increase was biggest contributor to velocity drop. i'm too inexperienced to have developed instinct. I've since hit all the remaining virgin brass with a mandrel and will load out a new batch bumping the charge to get the velocity up and hope for smooth seating forces.
bottom line, i need 100 for an upcoming ELR match and dont want to go back the 1.6" groups the hornady 1x brass delivered.
So far I've seen good results with N565
Berger 215 HTs
Fed 215 Mag Match Primers
78.9 gr N565
26” Barrel
Velocity is 2970 and I’m sitting .027 off the lands
10 shot SD was 6.8.
Seating depth test showed me a slight avg velo increase of 20fps and a better SD (.033 off lands) but I don’t believe it grouped as well.
I have found the 300 PRC to be a very good shooting caliber. I've shot 225 ELDM's and 230 LRHT's using H1000, N570 and RL26. The barrel likes RL26 but it's been impossible for me to procure. My favorite Load so far is Berger 230 LRHT over 75.4 grains of RL26 20 shot average is 2891 fps with a 7.8 SD
Just FYI:
www.snipershide.com
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
I haven’t used it, but everything I’m reading about SBHD powder seems like low fps.
I’ve seen several loads of well over 80gr using 210 bullets. They were getting pressure and only attaining barely over 2800fps
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On burn rate charts it is slower then retumbo, wonder how well it would do with heavier bullets
I need a math check here on neck tension using a 0.3070" mandrel, 0.3330" neck/shoulder bushing (SAC die), ADG 300 PRC brass with an average 0.0147" wall thickness, and accounting for 0.0005" spring back.
First operation on the SAC die is decap + ID neck mandrel sizing -
0.3070" tool, account for 0.0005" spring back against the working direction, I'm calling a 0.03065" ID and 0.3359" OD on the neck after this.
Second operation, neck size and shoulder bump in the SAC die -
0.3330" tool, assuming 0.3335" ID after 0.0005" spring back opposite of the working direction. 0.3335" OD - 2(0.0147") = 0.3041" ID.
0.3080" to 0.3085" bullet dia - 0.3041" = 0.0039" to 0.0044" neck tension.
Am I off at all here?
First operation on the SAC die is decap + ID neck mandrel sizing -
0.3070" tool, account for 0.0005" spring back against the working direction, I'm calling a 0.03065" ID and 0.3359" OD on the neck after this.
Second operation, neck size and shoulder bump in the SAC die -
0.3330" tool, assuming 0.3335" ID after 0.0005" spring back opposite of the working direction. 0.3335" OD - 2(0.0147") = 0.3041" ID.
0.3080" to 0.3085" bullet dia - 0.3041" = 0.0039" to 0.0044" neck tension.
Am I off at all here?
Math seems good but more complicated than I have used to measure neck tension.
My ADG 300PRC Virgin brass has a diameter of 0.334, so exactly what you are seeing. With a 230gr A-Tip, the diameter increases to 0.336, so neck tension of 0.002. Diameter on the A-tips was 0.3075”
I could be thinking about it the wrong way, but it feels right when seating the bullet.
I wasn’t planning on running a mandrel, just a neck bushing in the Redding dies.
Rifle is an Origin Long Action with a PVA Osprey 26” M24 1:9T stainless barrel on it.
Load data is in the attached picture. The highlighted cells without data are simply because I have only run virgin ADG brass so far and haven’t resized to set the should bump or decide on a trim length yet. Load data for the dog is raw meat.
Velocity didn’t increase in the first 90 rounds, but SD actually tightened from 9 down to 6 (all on virgin brass). It isn’t the fastest load, but shoots super well at 0.4-0.6” CtoC groups @100yds, maybe a hair tighter if I am shooting well. Velocity was measured with a Magnetospeed and the suppressor on. Took the rifle out to 1100yds with no issues without truing velocity (I dont have easy access to 1300+ to true it anyways).
This rifle hammers at night. Since CNVD-LR and M2124-LR clip ons are actually rated to 338 Norma (confirmed when Barrett won the Mk22 contract), I have shot it with my CNVD-LR. I can’t recall what those rifles weigh, around 20lbs I think, and this is 26 unloaded. Only shot 500yds with it, but damn, the flash from the A-tip hitting steel was bright enough to see even without night vision.
Load data is in the attached picture. The highlighted cells without data are simply because I have only run virgin ADG brass so far and haven’t resized to set the should bump or decide on a trim length yet. Load data for the dog is raw meat.
Velocity didn’t increase in the first 90 rounds, but SD actually tightened from 9 down to 6 (all on virgin brass). It isn’t the fastest load, but shoots super well at 0.4-0.6” CtoC groups @100yds, maybe a hair tighter if I am shooting well. Velocity was measured with a Magnetospeed and the suppressor on. Took the rifle out to 1100yds with no issues without truing velocity (I dont have easy access to 1300+ to true it anyways).
This rifle hammers at night. Since CNVD-LR and M2124-LR clip ons are actually rated to 338 Norma (confirmed when Barrett won the Mk22 contract), I have shot it with my CNVD-LR. I can’t recall what those rifles weigh, around 20lbs I think, and this is 26 unloaded. Only shot 500yds with it, but damn, the flash from the A-tip hitting steel was bright enough to see even without night vision.
Attachments
Yeah, I was ordering a new SAC Modular sizing die and didn't want to reorder components....so measuring more than I spend here
Also looking to bump up to the 4-5 thou neck tension per Alex Wheelers work on the subject. We'll see what SD's and ES look like for me.
I am second guessing myself and wondering if I should chase velocity a bit more. My guess is I am on a lower node. I pushed the powder to 78.5gr of Retumbo and velocity went up to around 2825-2850fps without pressure signs. But given how consistent this load seems to be, I am not sure if it is worth wasting more components to get 2850fps with a 26” barrel.Yeah, I was ordering a new SAC Modular sizing die and didn't want to reorder components....so measuring more than I spend here
Also looking to bump up to the 4-5 thou neck tension per Alex Wheelers work on the subject. We'll see what SD's and ES look like for me.
Thoughts?
I don't think it could hurt to prepare a 15 round, 0.1 grain increment ladder and see how far off of pressure you are. But, 2800+ on the 230 is pretty solid. If the gun is accurate and you're making hits at the ranges you shoot then a little extra velocity is just wasting powder and eroding your barrel more.
For a hunting rifle on the other hand I do believe in chasing speed. There's an additional need for it there. On a target gun, who cares how fast it's going (relatively) if you're hitting the ranges you need to with good groups.
Yeah that's kinda what I figured. Maybe I will run a 10x round groups at 78.5 and see how it shoots and how the velocity looks but if not, leave it alone.
I think that's a good move. On the other hand...I am doing some loading tonight and shooting tomorrow for a Badlands 205 grain SBD2 in my 20 inch 300 PRC over RL26, will report back how smokin hot I can get that thing
Got the 205 SBD2 to about 2850 and 190 LRX to 2950 out of the 20 inch 300 PRCA today with absolutely zero pressure signs. Going to load some more and head back to find the ceiling hopefully soon.
Edit:
My quick ladder on the 190 LRX was
RL26 (Grains) Velocity (FPS)
77 - 2,794
77.2 - 2,835
77.4 - 2,826
77.6 - 2,862
77.8 - 2,890
78 - 2,874
78.2 - 2,926
78.4 - 2,949
I counted 6 holes here, for sure fired the 8 above. No other holes on the paper, so assuming / hoping 2 holes in holes. Held POA on the ladder in search of nodes...I think I found the really big node
Edit:
My quick ladder on the 190 LRX was
RL26 (Grains) Velocity (FPS)
77 - 2,794
77.2 - 2,835
77.4 - 2,826
77.6 - 2,862
77.8 - 2,890
78 - 2,874
78.2 - 2,926
78.4 - 2,949
I counted 6 holes here, for sure fired the 8 above. No other holes on the paper, so assuming / hoping 2 holes in holes. Held POA on the ladder in search of nodes...I think I found the really big node
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I tried loading 10x rounds of the 78.5 of Retumbo with the same 230gr ATip in the ADG brass.I think that's a good move. On the other hand...I am doing some loading tonight and shooting tomorrow for a Badlands 205 grain SBD2 in my 20 inch 300 PRC over RL26, will report back how smokin hot I can get that thing
I got 5 in and knew it wasn't as good. Velocity jumped to 2846fps (no pressure signs) but SD in just that string went to 21. Not gonna work. Accuracy opened as well.
Sticking with 2790fps and the node it's in.
Against ~50 fps, I would say you definitely made the right call!
If you are using Redding Dies which bushing are you using for Lapua Brass?
Thanks
Truly considering a custom 300PRC build that is ready for sale but really concerned about being able to find magnum primers right now. Do you guys all just have stuff stocked up from when it was all easily available?
Up here in Canada. The only rifle primers that are available is the ginex crap.. and old stock that people have had sitting around for years and years. And they're Selling them for 600-1000 per Brick. Plus shipping..
FYI you can use large rifle primers just fine, it doesn't make a huge difference if any.
Slightly less bang, which means slightly more powder required. Unless you're shooting in extreme cold, they ignite the powder just fine. Of course, up there in Canada, that's certainly a possibility.
I do have a fairly small amount but do have some BR2's. I have seen a few posts saying they are good for this round. Do you agree?
I use exclusively BR2s. I found them to be slightly more consistent than 215Ms.
