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338-300 PRC... Sherman Improved!

I may need one also!!! I built a 300 PRC for elk/nilgai. But can never have too many rifles!!! Especially one that slings big lead at 3000 fps!!!

I should add to that, in a 22" barrel it's shooting 225's at 3k without pressure signs on multiple brass firings now. Haven't pushed it to the limit and I don't know that I have a reason to. Bore diameter efficiency is a real thing! 🤘🏼
 
I should add to that, in a 22" barrel it's shooting 225's at 3k without pressure signs on multiple brass firings now. Haven't pushed it to the limit and I don't know that I have a reason to. Bore diameter efficiency is a real thing! 🤘🏼
My 300 PRC is a 26" Proof CF with a big muzzle break, so not "brush" friendly. Better suited to be in a high rack truck in South Tx stalking nilgai or my son in laws backpack on the side of a mountain somewhere chasing elk.

This may become a good example of a true switch barrel situation. Straight 300 PRC for LR elk and 338/300 PRC for the big antelope!!!
 
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Very interesting, you've got me looking forward to working up a load for my 33 Nosler.
I bought a 100 rounds of the Nosler etip's back when brass was non-existant and I'm getting real close to needing to work up a load.
The 230eldx or the 225 accubond may even try the 225 ttsx
Very encouraging post
 
Very interesting, you've got me looking forward to working up a load for my 33 Nosler.
I bought a 100 rounds of the Nosler etip's back when brass was non-existant and I'm getting real close to needing to work up a load.
The 230eldx or the 225 accubond may even try the 225 ttsx
Very encouraging post

More testing to follow! If I had to bet, I'd say the 33 Nosler & 33 Sherman Magnum are pretty close. I'm going to do a little load work with 250 SMK's & H4831sc to compare against @Idaho Trecker 's 33 Nosler. He's using Peterson brass, mines with Lapua so premium brass on both too.
 
Speaking of 250 SMK's... they fit within the same freebore as the 225 AB, 230 ELDX, 250 EH bullets. Going to do a quick test for comparisons sake. Stay tuned!

20240423_195813.jpg


20240423_203154.jpg
 
Made it back out to finish pressure testing today. All loads were R26. I have the .312FB reamer. I hunt mostly Hawaii these days and even though it's hot, the temp swings very little. It was 79 degrees today and these are sea level speeds.

230 ELDx was a standout, but it's not the bullet I really hoped to use. The entire 230 ladder stayed within an inch. A decent node shows up at 86.0-87.0 and is around 3075fps. I got a slightly sticky bolt lift at 88gr of R26. I may end up with this bullet though as a 3000+ 230 ELDx is no slouch.

The 225 CE MTH was all over the place until the charges got compressed. 88.5-90 clustered very tight and speeds exceeded 3100. I need to try a faster powder, these results match KH's results with H10000. R26 and H1000 are #160 and 161 on the current burn rate charts. The loads are highly compressed as the powder was nearly at the base of the case neck!

270 ELDx didn't pressure out, but I also expected more speed. Rich achieved 2800+ with a 285 in his 24" gun and I was hoping for similar. I plan to try 82-85 in .5gr increments later. But I did get a cluster at 80.5-81.5 and 2700fps with a 270 isn't shabby.

I've got some 300gr Sierras to try, but I don't have high hopes given the long bearing surface. My goal was to run the heavy 338 pills faster than my Win Mag could and use that rifle as my project. My pet 338WM load was the 225 CE at 2950, so I didn't gain much with that bullet. But I gained about 150fps on the 230 and 250fps on the 270, so I'm liking the 33SM so far!

I need to trash my Magnetospeed. It's 10yrs old and lived a rough life…

R26225 CE MTH230 ELDx270ELDx
72.5NR
73NR
73.5NR
74NR
74.5NR
75NR
75.5NR
76NR
76.5NR
77NR
77.5NR
78NR
78.5NR
79NR
79.5NR
80No Reading (NR)NR
80.528362679
8128712699
81.528842681
82NR2721
82.5NR
83NRNR
83.528742950
8429022954
84.5NR3009
8529683049
85.529833035
862970NR
86.5NR3078
8730323083
87.5NR3157
883027Pressure
88.53072
893059
89.53107
903149
 
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Awfully tough to beat a good 33, I've been a monster fan of the 340 Wby since the 1980's. Great round, easy to work with. We normally used Schneider barrels cut to 23-25". For actions we used 70's, 700's and 98's.

I wore out 2 barrels on game and in shooting chucks at long range.

For the most part we built them to be in the 8 lbs to 9 lbs "all up" (scoped, rounds, sling). No breaks, or cans. If I did one again I'd go with a 20-21" barrel and set it up for a can.

First bullet I'd give a go would be the 250 Scenar, that bullet would be fantastic in the 33's!

We got great case life with Wby brass or 8 Rem mag brass (IE. good primer pocket life of up to 13 loadings b4 the pockets opened up enough to discard them.

As well we had very good barrel life, well up into the 2500 round range b4 they'd give up the ghost.

Have fun with this bugger (I can tell you are:)...

On a better note, you've mentioned a couple times using them on Big Alaskan game, what are you booked for and when?

Life's short, hunt hard!
 
Awfully tough to beat a good 33, I've been a monster fan of the 340 Wby since the 1980's. Great round, easy to work with. We normally used Schneider barrels cut to 23-25". For actions we used 70's, 700's and 98's.

I wore out 2 barrels on game and in shooting chucks at long range.

For the most part we built them to be in the 8 lbs to 9 lbs "all up" (scoped, rounds, sling). No breaks, or cans. If I did one again I'd go with a 20-21" barrel and set it up for a can.

First bullet I'd give a go would be the 250 Scenar, that bullet would be fantastic in the 33's!

We got great case life with Wby brass or 8 Rem mag brass (IE. good primer pocket life of up to 13 loadings b4 the pockets opened up enough to discard them.

As well we had very good barrel life, well up into the 2500 round range b4 they'd give up the ghost.

Have fun with this bugger (I can tell you are:)...

On a better note, you've mentioned a couple times using them on Big Alaskan game, what are you booked for and when?

Life's short, hunt hard!

That's great feedback on the 340 Wby! I should have made mention of that one previously too, it's a classic. The more comparison I do, the more similarities I'm seeing in performance between my 33 Sherman Magnum, 338-300 PRC, the 33 Nosler, and of course the 340 Weatherby. They're all splitting hairs I think so it comes down to a couple factors but mostly preferences.

As for the Alaska question, I hunt Alaska every year now. This year I'm heading up for Spring Grizz to hunt personally as well as assisting as a Packer/Co-Guide for the season. Also heading to Kodiak this fall for Sitka Blacktail.
 
Made it back out to finish pressure testing today. All loads were R26. I have the .312FB reamer. I hunt mostly Hawaii these days and even though it's hot, the temp swings very little. It was 79 degrees today and these are sea level speeds.

230 ELDx was a standout, but it's not the bullet I really hoped to use. The entire 230 ladder stayed within an inch. A decent node shows up at 86.0-87.0 and is around 3075fps. I got a slightly sticky bolt lift at 88gr of R26. I may end up with this bullet though as a 3000+ 230 ELDx is no slouch.

The 225 CE MTH was all over the place until the charges got compressed. 88.5-90 clustered very tight and speeds exceeded 3100. I need to try a faster powder, these results match KH's results with H10000. R26 and H1000 are #160 and 161 on the current burn rate charts. The loads are highly compressed as the powder was nearly at the base of the case neck!

270 ELDx didn't pressure out, but I also expected more speed. Rich achieved 2800+ with a 285 in his 24" gun and I was hoping for similar. I plan to try 82-85 in .5gr increments later. But I did get a cluster at 80.5-81.5 and 2700fps with a 270 isn't shabby.

I've got some 300gr Sierras to try, but I don't have high hopes given the long bearing surface. My goal was to run the heavy 338 pills faster than my Win Mag could and use that rifle as my project. My pet 338WM load was the 225 CE at 2950, so I didn't gain much with that bullet. But I gained about 150fps on the 230 and 250fps on the 270, so I'm liking the 33SM so far!

I need to trash my Magnetospeed. It's 10yrs old and lived a rough life…

R26225 CE MTH230 ELDx270ELDx
72.5NR
73NR
73.5NR
74NR
74.5NR
75NR
75.5NR
76NR
76.5NR
77NR
77.5NR
78NR
78.5NR
79NR
79.5NR
80No Reading (NR)NR
80.528362679
8128712699
81.528842681
82NR2721
82.5NR
83NRNR
83.528742950
8429022954
84.5NR3009
8529683049
85.529833035
862970NR
86.5NR3078
8730323083
87.5NR3157
883027Pressure
88.53072
893059
89.53107
903149

Thanks for sharing!
 
Update on the 250 SMK + H4831sc testing. Looking pretty solid!

20240427_145537.jpg


Charge weights of 79/80/81/82/83 gr of H4831sc all nearly touching at 100 yards. Tells me that this combination will absolutely show good accuracy. 83 gr began showing a faint Ejector mark, and 84 gr was a compressed load. So great case fill too. I'm going to load up some more at 80/81/82 to shoot some three shot groups.

Velocities for reference:

78 - 2726
79 - 2738
80 - 2788
81 - 2798
82 - 2835
83 - 2893 - faint EJ
84 - 2917 - " " & compressed
 
Update on the 250 SMK + H4831sc

It shoots!

Note: on charge weight 81 gr, you'll see that low dropped shot... called it before I saw it. Bipod budged as I broke the shot. It was me.

If I were to pursue this combo further I would re-shoot 81 for sure, and maybe even go load up more at 80, 80.5, 81 gr and do some larger sample testing to really hone in.

Really happy with what I'm seeing with 225/230's so far though, and beings it is a light weight big bore that I might run suppressed too, I'll stick to 200-230 class on this rig. Noticeable increase in recoil on the 250's for sure!

20240427_145517.jpg
 
Nice shooting with the 250s. I need to try some of that weight class to see if my FB has any measurable advantages with that class pill.

I agree the 340 Bee, 338/375 Ruger, 33Nos and 33 SM are all very similar. Kinda like 300WM, 30 Nos, and 300 PRC. Each has minor differences to keep us all talking!!
 
Nice shooting with the 250s. I need to try some of that weight class to see if my FB has any measurable advantages with that class pill.

I agree the 340 Bee, 338/375 Ruger, 33Nos and 33 SM are all very similar. Kinda like 300WM, 30 Nos, and 300 PRC. Each has minor differences to keep us all talking!!

Worth a shot on the 250's! I think the 250 gr and heavier options would be great in a longer barreled heavier setup. 24"+ barrel, 10-11lb scoped would be a pretty sweet setup for 250's.
 
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