My dream platform for 7 saum/7 max.
nuke XM length action in an XLR element with Proper XM mags and a 28-30” heavy Palma.
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7-300 PRC Initial Results - Winner
- Thread starter flounderv2
- Start date
nuke XM length action in an XLR element with Proper XM mags and a 28-30” heavy Palma.
I throated mine a little longer for use of the heavies only.
Berger 195 just touch at 3.225. Going to load at .015 jump to work up a load.
Wow only 50-60 FPS. If it doesn't pan out than off to the 28 Nosler.
What powder and bullet?
Could be a slow barrel
I think Rich’s speeds are a best case scenario, when researching the Sherman’s lots of people’s speeds fell short.
That’s why I went 7 saum.
I’m thinking one of the speedster powders like R26, N565 and N570 would be a necessity.
I also have a Proof 1-8 26 inch. Did you throat it long or go w reamer specs? Jump or touch or jam on your loads? Loading test loads tonight. Was going to load a couple up to 70 grains of N570 if i don't compress before that charge weight.
I was thinking I might have derailed it some by asking questions about other 7 mm calibers. Sorry If I did.
Yes, they say spring of 2021 but we shall see.... Looking forward to the 300PRC though.
www.lapua.com
New Lapua Brass Cartridge Cases for 2021
Lapua, world-renowned for producing the finest cartridge cases and ammunition products, is happy to announce the addition of 6.5 PRC, .284 Winchester, .300 Winchester Magnum, and .300…
www.lapua.com
ADG has been making 300 PRC brass for a while now. Top notch stuff.Yes, they say spring of 2021 but we shall see.... Looking forward to the 300PRC though.
New Lapua Brass Cartridge Cases for 2021
Lapua, world-renowned for producing the finest cartridge cases and ammunition products, is happy to announce the addition of 6.5 PRC, .284 Winchester, .300 Winchester Magnum, and .300…
So I just ran across this post today, and after reading all three pages I have one quick thought. I’ve seen a lot of 28 Nosler comparisons and from a performance standpoint I can understand it. But another aspect to new or wildcat cartridges is the availability of bullets and brass, or how much alteration to existing brass is necessary. Also, what does the brass cost. When I was looking at 28Nos I pretty much kept getting hung up on the cost, $3+ each. Compare that to PRC brass and the choice is easy for me. More and more mfgs are getting on board with the PRCs which will drive the price down more and increase availability. Maybe this doesn’t matter to all you dudes, but it’s an important consideration for me and if the performance is 6 and one-half dozen, the edge goes to PRC. Just a thought
There is no such thing as cheap brass, and there is no such thing as expensive brass. By the time you get done culling and fire forming cheap brass, it's not so cheap. By the time you've shot a $2 piece of brass 10x, it was 20 cents a shot in a round where bullets were 60 cents and every shot was $1 in barrel life.
The 28 Nosler has about 101 grains of water capacity, the 7/300 PRC about 95, a 7 Remington Mag or WSM is about 82, ADG SAUM is 73. For a given pressure and barrel length, velocity is going to follow case capacity and it's going to be at the expense of barrel life. With jacketed bullets, loads that win the internet speed game tend to be useless once you start keeping score.
A straight shot with a piece of 300 PRC brass in a one piece 7 SAUM die gives neck runouts in the .008-.010" range. Stepping it down with a 300 PRC bushing die in .006-.007" steps and then finishing with the 7 SAUM die keeps them all below .003" and most below .002". It's more work, but you only have to do it once and the brass is gtg from the first shot.
The 28 Nosler has about 101 grains of water capacity, the 7/300 PRC about 95, a 7 Remington Mag or WSM is about 82, ADG SAUM is 73. For a given pressure and barrel length, velocity is going to follow case capacity and it's going to be at the expense of barrel life. With jacketed bullets, loads that win the internet speed game tend to be useless once you start keeping score.
A straight shot with a piece of 300 PRC brass in a one piece 7 SAUM die gives neck runouts in the .008-.010" range. Stepping it down with a 300 PRC bushing die in .006-.007" steps and then finishing with the 7 SAUM die keeps them all below .003" and most below .002". It's more work, but you only have to do it once and the brass is gtg from the first shot.
Why join the fan boi club?
The 28 Sherman requires stepping down the supplied brass from 30 caliber and then firing forming, just like a 7/300 PRC. If I wanted more case capacity, there is the 28 Nosler without the necking down or fire forming step. But I didn't want any more case capacity.
Adding a fire forming step to a case that can't have any more taper taken out of it to get a 40 degree shoulder is a total poser move. I've done a couple 338 Lapua based 40 degree wildcats and they're not worth the trouble to form or in sizing afterwards.
The 7/300 PRC is a simple neck down wildcat that uses brass, headspace gauges, and dies that are readily available. Well, as readily available as anything is today. It fills a pretty big gap in case capacity between the 7wsm and the 28 Nosler. The 7 LRM is probably a smarter case capacity, but the limited edition pricing of components was a turn off.
338 prc aka 338/375 ruger is no slouch. Got 2830 with 300gr Berger’s and 30” tube in mine. Not bad for 78gr h1000
i built my wildcat 7mm based on 197gr pills. the case capacity is a 5-10gr more than 28 nosler. Should i have done the 28 nosler...but i do what i enjoy and thats solving problems.
if you're still stuck on 150-168gr pills then stick with the smaller volume...e.g. 7m-08.
just my 3 cents
if you're still stuck on 150-168gr pills then stick with the smaller volume...e.g. 7m-08.
just my 3 cents
i spend about $1.50 for each brass then another 4 hours per 20 cases modifying for my 7mm wildcat. I'll lose about 20-50% but im getting better. 65 wsm, necked down from 300, looks straight forward but isnt. About 50 cases per hour and $1.75-$200
Cool postI'll be doing most updates on my FB page so feel free to follow there but I've also copied all the initial data below.
Some of you may know that I had a reamer made to neck down the new 300PRC to 7mm to see what it would do. I.e. A 7-300prc . I got it back from Alamo Precision Rifles on Friday and was able to put about 30 rounds on it so far and the results are impressive. The case shape and length provides some added benefits over the 28 nosler imo. Speed wise it seems to me that it can easily match or beat the 28 nosler with less effort and lower pressure loads. The 28 nosler advertises it can run a 175 around 3125 and but I'm hearing guys say 195s at 3140-3150 with faster powders and in sure this is a warm if not hot load. I'm curently pushing 184 bergers at 3175 with a slow powder and zero pressure and the Barrel isnt even broken in yet. At these speeds it should already run a 195 at 3140-3150 and also no pressure.I played with it a bit over the weekend using retumbo and 8133 and with 82gn 8133 which is a slightly compressed load, Im at 3173 avg with an SD of 4.5 with 184 hybrid. Barrel is a 28" Hawk Hill CustomNo pressure even with water test. For those that dont know, the water test is pouring water on the case to simulate shooting in rain and if you have a hot load you'll blow primers and get a locked up or hard to open bolt in a heartbeat. I had zero issues and it opened like a normal round. Retumbo is a bit faster still no pressure. This thing is stupid light recoil for the speeds. My original goal with this was to push a 180 pill at a mild 3100-3150 with a powder that gave me almost full case fill and no pressure and it seems to be working spot on for that. Ill post more as I keep testing. brass life test with the same load made it to 7 firings before I had indications of loose primer and thinning case web. I think with something like RL26 or H1000 you could probably push a 180 in the high 3200s to mid 3300s or a 195 around 3200 without being too hot of a load.
Update 1 - 7x firings with 81.4 of 8133 was averaging 3155 with the 184. Everything felt good until the last resize and primer went in pretty easy. Checked the case and saw the faint line of death around the base. Checked the inside and you can feel it getting thin. I wouldnt push it past 5 to be safe depending on your load.
Also realized the Hornady 300 PRC sizing dies are no good. They dont size far enough to the base at all even if you push a piece back to factory dimensions. Hornady you better check your PRC dies or you're going to have a lot of people pissed off they have a sticky bolt on any reloads because your dies arent sizing enough. They arent even changing the dimensions of the case anywhete close to the base from a fired piece to resized . I thought they were sizing way to easy for such a large case and now we know why. They need fixed ASAP.
Update 2 - Between the seating die being a bad design imo which also doesnt work with a Forester Co-AX without chopping down the seating stem, the fact that the sizer doesnt size properly or that the hole diameter for the bushing is massively oversized and causes crazy amounts of neck runout unless you teflon tape the bushing, I'm done with the Hornady "Match Grade" dies. Unfortunately they were the only ones making PRC dies when I needed to get them. I'll probably give them away at some point or maybe do something really silly with them out of frustration. I spoke to Dan Warner today at Warner Tool Company and I'm going to have him make me a set of custom dies. If you havent seen their custom dies, they truly are a work of art with no comparison. I've been considering a set of his dies for a while now and finally going to pull the trigger.
I'm pretty interested in the 7-300 prc now, especially with lapua brass coming out.
Do you have any updates on your setup?
Real curious how many rounds you've put through it and how the throat looks.
Once you shoot those alcos you will see that the bc stated is not even a dream. I have a bunch of lost river pills with overstated bc's They are not as exaggerated as the alcos but still ,050 to ,075 higher than what the drops indicated
I recently shot the Cayugas, going into it with the same mind set and was blown away. would love to see them in a hot rod caliber
I believe that I shot some warner tool stuff and it lives up to the hype. The over inflated bc's of the early 2000's and before have been weeded out for the most part. Every year someone posts up those friggin alcos with their bs numbers and the soft heads don't even look at the form factor and restate the bs number. If they shot them at 308-300 winny velocites .5-.520 in a 10tw. I have lost rivers which are as close as can be in form factor and dimensions and they state .560-.575(I'd have to look on the 165/8s} and I've never had them shoot as well in the wind as the 175smk. I still have a bunch of them in multiple calibers. 270 30, 338 and 375 or 416(again not sure)
I run mine through a .313 bushing in 300PRC die and load them. I haven’t had any issues with neck bulge yet.
I am running 180 hybrids at 3125 with a fairly mild load of H1000. I’m getting ready to test some IMR 7977 and H4831SC. I doubt the 4831 is going to be all that spectacular, probably a bit fast for this cartridge, but I’ll give it a go.
How many loads have you fired with your brass, any issues with runout sizing down that much with a bushing?
It seems like you'd at least have a donut formed at the base of the neck, when I formed 7 saum brass to 6.5 I ran them through a .264 expander mandrel and turned the thick brass off near the base.
Pretty impressive speed!
How long is your barrel?
I’m on the second firing on most of it, I have a few on their 3rd. Hornady brass, so far it’s all still in good shape. I am waiting for some ADG to show up. There was a tiny bit of donut when I sized them the first time, but after fire forming it is not even noticeable. After the first firing my neck runout is pretty good for not using a mandrel, avg runout is around +/- .002 on once fired, annealed brass. I have been pleased so far with speeds, we will see what some different powders will do. I’m running a 28” Bartlein 8 twist.
Same here, ran it through a prc die with a 7mm bushing. Easy peasy
Time will tell, I don’t think it will be horrible though. Sounded like @flounderv2 was seeing pretty promising results as far as barrel life goes. I don’t have enough rounds through mine yet to even make an educated guess.
