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Posted: 2/15/2026 3:23:12 PM EDT
A little project that has been in the works, because people keep asking about 'supercharging' the SOCOM... and maybe bourbon played a role.  When the .458 SOCOM was first developed, because it had to fit in the AR15 platform, it meant that performance was going to be reduced, as the maximum chamber pressure had to be kept low enough to work with the smaller AR15 bolt. Plus it had to fit the .223 mags, keeping the overall length to a maximum of around 2.3". A number of folks played with the SOCOM in other platforms, including bolt guns, which allowed pushing things, but just not the same. Some hybrid platforms came about, but even for those, the loaded length was limited to that of the AR15 mags. Using brass that is dimensionally almost the same as the SOCOM, but takes rifle primers and allows pushing pressures to 60k psi, things can get interesting. Resized to SOCOM, and off we go. Add to that a longer overall loaded length, and it gets even more entertaining. Now lets put that in a semi auto platform, with a fast twist barrel. Attached File So what then do some of these loads look like and what are the numbers? Attached File Left to right - 275 gr 'hollow point' for reference - I think we missed an opportunity here, if that hexagonal opening were the same size as my hex tools....  - standard 300 TTSX but loaded to 60 k psi - we clocked this at 2,100 fps from the 16" rifle - sabot load loaded to AR15 length - TBD - Barnes 500 gr Spitzer - should do about 1550 fps from a 16" - that same 275 gr HP but with a 62 gr .223 seated - TBD - the sabot load at longer length with a 168 SMK - should do 2600 fps from the 16" - the Cutting Edge 700 gr LAZER... that thing is sexy - the 700 gr loaded to 3.500" - single load through the ejection port - these would be subsonic, needing the fast twist barrel The mags are still a bit finicky, we can load 3 rounds in the existing ones, but we had some discussions at SHOT and hopefully some better options will materialize... Attached File We'll do some more testing and get some more actual range results on some of the projectiles. Interesting to note that we have fired 'standard' SOCOM loads and these cycled as well... just not as much velocity, obviously. |
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Originally Posted By PreacherOfGadget: I'm curious to see how it performs. Maybe I missed something, but is that just an ar-10/.308 platform or is that a custom length receiver? Standard COTS noting special DPMS LR... well, custom engraved on the other side. Other components are all 'stock'.... |
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"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
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Originally Posted By ELittlefield: Just today I was fantasizing about a 450 BM or 458 SOCOM necked down to 6.5 or 224 caliber. There must be a reason it's not really done. I kind of got excited when the SFAR came out , but any Smith i spoke to wasnt convinced there was enough meat up front even with the spiffy bolt . A std AR10 shouldn't be too much of an issue . * I have similar musings but bushmaster necked to 375 ... then im like "I cant afford that !" ...and then it dissipates. I do have 375 socom , so that helps some . Haha |
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Originally Posted By 9D1Alpha: Thats big enough you could replicate the 8mm CETME aluminum bullet . Get the high BC profile at half the weight ...and cheaper aluminum. That 700 grainer? We could ask them... We did the 275 grainer in AL, they come in at 158 gr and we fired them from 'standard' pressure and length loads. Somewhere there is footage of these being fired in the desert at dusk, despite the custom 'Flaming Pig' KFH on my 9.3" upper, the muzzle flash washed out the camera briefly. Something about 6 ft of muzzle flash sending that AL projo at over 3000 fps from an SBR... Attached File |
Be careful when the boss asks "Have you ever been to ...?"
"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
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Originally Posted By 9D1Alpha: I kind of got excited when the SFAR came out , but any Smith i spoke to wasnt convinced there was enough meat up front even with the spiffy bolt . A std AR10 shouldn't be too much of an issue . * I have similar musings but bushmaster necked to 375 ... then im like "I cant afford that !" ...and then it dissipates. I do have 375 socom , so that helps some . Haha I suppose the .500 Phantom and .470 Rhino are not known to them? Where is BigBoreHK when you need him.... Attached File Attached File Attached File Attached File |
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Originally Posted By MartytW: I suppose the .500 Phantom and .470 Rhino are not known to them? Where is BigBoreHK when you need him.... https://www.ar15.com/media/mediaFiles/2963/500Plineup_jpg-3714023.JPG https://www.ar15.com/media/mediaFiles/2963/IMG_0206_JPG-3714024.JPG https://www.ar15.com/media/mediaFiles/2963/470_Rhino_1_JPG-3714026.JPG https://www.ar15.com/media/mediaFiles/2963/Rhinos_jpg-3714027.JPG Originally Posted By MartytW: Originally Posted By 9D1Alpha: I kind of got excited when the SFAR came out , but any Smith i spoke to wasnt convinced there was enough meat up front even with the spiffy bolt . A std AR10 shouldn't be too much of an issue . * I have similar musings but bushmaster necked to 375 ... then im like "I cant afford that !" ...and then it dissipates. I do have 375 socom , so that helps some . Haha I suppose the .500 Phantom and .470 Rhino are not known to them? Where is BigBoreHK when you need him.... https://www.ar15.com/media/mediaFiles/2963/500Plineup_jpg-3714023.JPG https://www.ar15.com/media/mediaFiles/2963/IMG_0206_JPG-3714024.JPG https://www.ar15.com/media/mediaFiles/2963/470_Rhino_1_JPG-3714026.JPG https://www.ar15.com/media/mediaFiles/2963/Rhinos_jpg-3714027.JPG You have to remember the SFAR comes in at the ar15 diameter bbl/bbl extension. Id like to know if the 408 cheytac 416 thumper would fit in the ar10 mag . * 505 Gibbs based i think . .640 rim |
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.500 Phantom used a standard magnum size rim, back when those bolts were still being made - .532". Case diameter was the largest that would fit the AR10 extension at 0.619" The Rhino cases were longer versions based off .500 Jeffery, similar to the Phantom, just longer. Just costly to make the cases... We did .338, .375, .416, .458, and .475, the latter being the Rhino. Still have the dies for several of them sitting here. Then there is the .510 Phalanx, but that is a whole other story.... we had an old M1918 BAR that we were going to rebarrel.... |
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I've wondered recently if a 3d printed metal mag wouldn't help . The sintered powder version has been out for a little bit , but now theres a version with the metal infused in a "paste like" substrate that gets baked away later . Cost could be somewhat of an issue , but the low volume nature of the whole thing might make it less so . And , the dimensions could be maximized for "perfect" function . Tech is always moving along . |
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Originally Posted By 9D1Alpha: I've wondered recently if a 3d printed metal mag wouldn't help . The sintered powder version has been out for a little bit , but now theres a version with the metal infused in a "paste like" substrate that gets baked away later . Cost could be somewhat of an issue , but the low volume nature of the whole thing might make it less so . And , the dimensions could be maximized for "perfect" function . Tech is always moving along . Tim, who worked with us quite a bit before our little Odyssey took us all over the globe, has done a fair bit of work with 3D printed mags. I have one sitting here, it did not work with the SOCOM case as the case diameter is just a hair too little. For larger cases it works, however, in our experience those also will work with the standard mags. The nice thing is that you can print rather stout walls so that helps prevent any bulging. If I were a bit more handy with sheet metal and welding equipment, I'd try and cobble some test mags, but I have enough trouble with balsa wood and pocket knives... |
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"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
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Marty, I don't know if it matters anymore but KAK does still make a "magnum" sized bolt for the LR-308 in case you are contemplating resurrecting the Phantom and Rhino from their death beds. It has double ejectors if that matters and is $150 for just the bolt assembly, but at least if my Rhino or Phantom ever breaks a bolt, they are still available. The old DPMS bolts in mine are still going strong so it is hard to justify getting a couple of spare bolts "just in case." It's not like they get shot that much anymore due to the cost of Jeffrey brass and forming for the .470R and while I still have a couple hundred of the .500 Phantom cases from that one run you did over a decade ago, when they are gone that's it. That one company that said they were going to make some Phantom brass, Quality Cartridge??????, never came through and never answered emails so after a year or two of trying, I gave up on them. |
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Originally Posted By Big-Bore: Marty, I don't know if it matters anymore but KAK does still make a "magnum" sized bolt for the LR-308 in case you are contemplating resurrecting the Phantom and Rhino from their death beds. It has double ejectors if that matters and is $150 for just the bolt assembly, but at least if my Rhino or Phantom ever breaks a bolt, they are still available. The old DPMS bolts in mine are still going strong so it is hard to justify getting a couple of spare bolts "just in case." It's not like they get shot that much anymore due to the cost of Jeffrey brass and forming for the .470R and while I still have a couple hundred of the .500 Phantom cases from that one run you did over a decade ago, when they are gone that's it. That one company that said they were going to make some Phantom brass, Quality Cartridge??????, never came through and never answered emails so after a year or two of trying, I gave up on them. Hey Big Bore! Glad to hear that there is still an option, albeit pricey, for a magnum bolt. The Phantom will remain in its grave, there are specific reasons for not resurrecting it. The Rhino, we'd have to see if brass could be cheaper, I have some other ideas for that. I don't think Horneber is still making brass (Dieter was old 20 years ago, I'd have to see if he is still alive), and neither Quality nor Jamison ever were able to produce it. Not sure if those two companies are around these days, either. But first we need to get the magazines resolved, so I need to chase that down.... |
Be careful when the boss asks "Have you ever been to ...?"
"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
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You might want to contact Bishop Ammunition and Firearms. link They developed a round very similar to the .470 Rhino, the .475 Bishop Short Magnum or .475 GAR. They use Roberson Cartridge Company out of Texas to CNC their cases and it is very similar in performance, but not interchangeable with, the .475 Rhino. With the Rhino, I ended up being able to get about 1900-2000 fps with a 500 gr. RN without getting pressures so high it enlarged the primer pockets or tearing the rims off the case. Initially, as you might recall, the guy who did the workup on the .470 R was getting a lot higher FPS than I got but he was also tearing the rims off the cases. IMO he was using the wrong powder because when I tried his loads, I could not get anywhere near his velocities without having pancake flat primers and enlarged primer pockets, so being each case costs about $10 to buy, turn, and form, that's too much to only get one or two loads out of it. I backed it down and switched powders so the case life is now a lot longer but velocities are slower too. It is more like a .458 Win mag now, throwing a 500 gr. bullet at 1900-2000 fps instead of the 2200 fps hoped for at the beginning. QL was way off on its predictions on this round. Bishop is getting 2500 fps with a 390 gr. CNCed copper bullet but I have not tried bullets lighter than 500 gr. since I was interested in cloning the .470 Nitro Express with 500 gr. bullets, not shooting for break neck speed with lighter bullets. I felt the Rhino was best suited for keeping rhinos, elephants, and cape buffaloes out of the garden and for that I needed the heavier 500 gr. bullets. This info is also posted on their web site and he has an interesting bolt action and lever action rifles in .458 SOCOM you might enjoy checking out.
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I looked at the Bishop round and already pulled some 338 LM brass out and started playing with it in the other Rhino dies. The problem I encountered is that the 338 LM brass at 0.59" diameter will NOT stay put between the lips of either MagPul or metal .308 mags.... You have to go to the larger (Phantom/Rhino) case diameter, OR back to custom mags. If we can get the new mags produced, it opens up WAY more options as now all cases from 0.53" diameter AND LARGER will have a way to feed well .... |
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The Bishop round did look a little floppy in the mag on one video where I watched them load up and shoot .  Failed To Load Title The 338LM fits an ar15 mag , though the feed lips could probably be shaved a few thou on each side to let the case ride a hair higher like the socom . Front of the mag would need opened up and a box extension added. |
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Originally Posted By 9D1Alpha: The Bishop round did look a little floppy in the mag on one video where I watched them load up and shoot .  https://www.youtube.com/watch?v=bUnftLHKeJgThe 338LM fits an ar15 mag , though the feed lips could probably be shaved a few thou on each side to let the case ride a hair higher like the socom . Front of the mag would need opened up and a box extension added. BigBore has done a lot of work on finding good ways to feed the SOCOM size in the AR10, including sleeved mags, etc. Trick is finding something that allows the AR10 lugs to clear the lips, but then still properly retain the cases and make sure they don't nose dive. I believe he found himself utterly frustrated...  I am about to slaughter an old metal 762x39 mag for the AR15 and push the remnants into a MagPul 308 mag to see what that does...  I am really hoping our discussions at SHOT bear fruit, as the results would be far more attractive, however, there is the 'chicken and egg' aspect - companies are reluctant to invest unless they anticipate good ROI, but sales of any such uppers/rifles are stifled by a lack of suitable mags... chicken, egg. 
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Be careful when the boss asks "Have you ever been to ...?"
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The chicken/egg analogy nailed it. With my .375 GRRR I found it was dead on arrival because I could never find a mag or modify a mag so it would work. It labored in the good idea/bad idea box for over two years until Duramag came out with their .400 Legend magazine. My .375 GRRR is based on the 6.8 case but is straight walled so no mag with a front side rib would allow it to stack properly and the .350 L mag for some reason or another would not feed them either. When I tried them in the .400 L mag, I swear I heard angels sing. Feeds like they were made for it so the only problem now is they (Duramag) does not make them in capacities over 10 rounds. Legally for deer hunting, that is all we are allowed to have regardless of magazine size or number of rounds on our person while hunting, but I'd still like to have the option for a higher capacity mag for kicks and giggles. But...Duramag told em a few months back that unless interest and sales pick up for the .400 L, it is unlikely they will make a magazine with a higher capacity than 10 rounds. Bummer. I would love to buy a metal 3D printer but unless I win the lottery, that's not going to happen. Think it would help if I bought a ticket??? On the Rhino and Phantom, the only mags I could really get to work halfway decently is the old DPMS metal mags with tweaked feed lips since the feed lips are open at the back as well as the front. If the feed lips are closed at the back then they cannot be tweaked much and that causes a problem. The DPMS mags feed the Rhino just fine and worked OK with the Phantom so long as I used the M33 ball bullets. With shorter bullets the mags need a spacer in the front or they would unstack under recoil and not feed for crap. The long M33 bullets kept the cases in place but you cannot exactly hunt with the M33 bullets. But they are great for breaking things and DAMN, they look impressive! .470 Rhino on left with 500 gr. SP, .500 Phantom on right with M33 ball. Attached File |
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Just for grins, IF we could these mags that fit the SOCOM case... it so happens that the 338 RCM has the same case diameter. Now, call me crazy, but I'd be pretty giddy about a 10-shot, detachable box mag fed, semi auto modern sporting rifle in 338 RCM.... I tried conveying that same during discussions at SHOT and follow up Email.... and I can only imagine the wildcats that would 'sprout up' if word got out. I can see a 375 being pretty fun, essentially a short version of the 375 Ruger... And Ruger themselves might find it intriguing.... and I'm sure someone would want to make a .308 version, as well as a 6.5 version... |
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Originally Posted By MartytW: Just for grins, IF we could these mags that fit the SOCOM case... it so happens that the 338 RCM has the same case diameter. Now, call me crazy, but I'd be pretty giddy about a 10-shot, detachable box mag fed, semi auto modern sporting rifle in 338 RCM.... I tried conveying that same during discussions at SHOT and follow up Email.... and I can only imagine the wildcats that would 'sprout up' if word got out. I can see a 375 being pretty fun, essentially a short version of the 375 Ruger... And Ruger themselves might find it intriguing.... and I'm sure someone would want to make a .308 version, as well as a 6.5 version... A 375 RCM would be pretty neat . I like the 375 in that whatever your bullet weight is , thats your SD as well. |
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Originally Posted By MartytW: Just for grins, IF we could these mags that fit the SOCOM case... it so happens that the 338 RCM has the same case diameter. Now, call me crazy, but I'd be pretty giddy about a 10-shot, detachable box mag fed, semi auto modern sporting rifle in 338 RCM.... I tried conveying that same during discussions at SHOT and follow up Email.... and I can only imagine the wildcats that would 'sprout up' if word got out. I can see a 375 being pretty fun, essentially a short version of the 375 Ruger... And Ruger themselves might find it intriguing.... and I'm sure someone would want to make a .308 version, as well as a 6.5 version... I know it's not the same thing but have you seen the GLFA(Great Lakes Firearms & Ammunition) long action AR's? Tony Rumore has messed with them a bit. This vid is a 375 RUM and I think he did another with a 300 PRC.  Tromix 375 Remington Ultra Mag AR-10 (Great Lakes GL-10) |
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Originally Posted By MartytW: That 700 grainer? We could ask them... We did the 275 grainer in AL, they come in at 158 gr and we fired them from 'standard' pressure and length loads. Somewhere there is footage of these being fired in the desert at dusk, despite the custom 'Flaming Pig' KFH on my 9.3" upper, the muzzle flash washed out the camera briefly. Something about 6 ft of muzzle flash sending that AL projo at over 3000 fps from an SBR... https://www.ar15.com/media/mediaFiles/2963/IMG_1057_JPG-3714021.JPG Originally Posted By MartytW: Originally Posted By 9D1Alpha: Thats big enough you could replicate the 8mm CETME aluminum bullet . Get the high BC profile at half the weight ...and cheaper aluminum. That 700 grainer? We could ask them... We did the 275 grainer in AL, they come in at 158 gr and we fired them from 'standard' pressure and length loads. Somewhere there is footage of these being fired in the desert at dusk, despite the custom 'Flaming Pig' KFH on my 9.3" upper, the muzzle flash washed out the camera briefly. Something about 6 ft of muzzle flash sending that AL projo at over 3000 fps from an SBR... https://www.ar15.com/media/mediaFiles/2963/IMG_1057_JPG-3714021.JPG I had to think about that 700gr for a minute. At first I envisioned the copper belt with a 2-piece aluminum center section that threaded together in the middle of the belt ... I suppose a male/female connect press fit would be more expedient. The 700gr profile would come in 300-350ish gr and have the gyroscopic benefit of the belt as well as the bearing surface on the rifling per original CETME bullet . The thing id look to try to prevent is leaving a belt in the bore ... |
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Originally Posted By 9D1Alpha: I had to think about that 700gr for a minute. At first I envisioned the copper belt with a 2-piece aluminum center section that threaded together in the middle of the belt ... I suppose a male/female connect press fit would be more expedient. The 700gr profile would come in 300-350ish gr and have the gyroscopic benefit of the belt as well as the bearing surface on the rifling per original CETME bullet . The thing id look to try to prevent is leaving a belt in the bore ... Had to do some research on the CETME bullet. I like the threaded Al 'top + bottom' with Cu 'belt' idea. The entire 700 gr Cu bullet would be about 221 gr if made of Al 6061. I think you could keep the composite Al-Cu version to 300 gr. But if you look at the numbers that the 300 TTSX gave with the high pressure loads, that would not be all that interesting. I would shorten the overall projectile to where COAL would be 2.8" rather than 3.4" with the 700 gr. That would get closer to 200 gr total projectile weight and would give far higher velocities. Question is, for what purpose? SD is low. Velocity is high, but these will act more like 'Spotter' rounds, giving a bright flash upon impact. |
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[b]Originally Posted By Question is, for what purpose? SD is low. Velocity is high, but these will act more like 'Spotter' rounds, giving a bright flash upon impact. I guess the proportions of the materials would need tweaked towards a useful purpose while retaining possible benefits. Improved BC and velocity Substitution of aluminum for copper (5:1 cost factor ) The trick would be retaining enough copper to give a sufficient SD for hunting light game ...270-280gr for .200ish I think simplification to an aluminum nose cone with a rod ( journal size variable to adjust bullet weight ) that extends to the base , attaching to an aluminum boat tail would do it. Maybe toss a lead washer between nose cone , copper, and base to save a bit more copper and tailor weight further .... * little lead flywheels on an aluminum axle ... |
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I did a cat years ago based on the .325 WSM case cut to 1.800 inches and necked up to .358. for a COAL of 2.800 inches. I have tried and tweaked every .308 mag on the market and none of them will load/feed more than 5 rounds. I even went so far as to try and put an AR-15 mag with the front cut out in an LR-308 mag so they would single stack. That worked out about as well as you can imagine. I tried shimming the sides of another LR-308 mag so they would single stack but that was way too much work and only very limited success, I could maybe get 6 rounds to work when the stars and planets were in conjunction. A 3D printed LR-308 magazine with thick walls so the rounds would single stack and not bulge the sides of the magazine would be the bee's knees. So if you make one, put me on your mailing list. Another "failure" I had was having Thomas make me a 12" barrel for my Striker blind magazine pistol, throated so I could load a 500 gr. RN and 525 gr. WFN out to 2.8 inches and raise the pressures significantly. I ran into two problems. Using the standard .458 SOCOM case, by the time I got to QL predicted 50K ish pressures, primer pockets started getting loose, recoil was severe, and I had gained very few fps. SR primers in the .458 HAMR case likely would solve the loose primer pocket problem like it did with some 6.8 SPC loads I was loading that were flattening primers with LR primers but when I switched to cases with SR primers, no pressure signs were seen at all on the primers. The second and most damning problem, that Striker pistol with its space gun wood stock is not very ergonomic and the recoil, even with a really good brake Thomas made me, was more than my arthritic hands could handle, so my loads went back to standard 36K pressures and velocities with lighter bullets. Attached File |
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The magazine issue reminds me of the 30 Rem AR . The magazine seemed as an afterthought and the solution was slop. Another possible slop solution would be EDM section an LR308 mag and take out 0.2ish . Laser weld the new halves back together . Leave the mag release bump side in contact with the magwell as designed and add the 0.2ish as a shim on the outside of the right hand side of the mag ( or shim the magwell). That keeps everything uniform and retains functioning mag ribs . Would need clearancing in relation to the bcg and feed lips im sure . And followers...and floorplates ... Next up, an in house vertical lathe and cutting tool for extractor grooves and rims . Id like this one myself , for making 7-30 waters rimless out of 375 winchester brass. That , and maybe putting .535 rims on 338norma/lapua . * the recent Colt MARS reproduction... EDM cut the ar15 mag and extend the front rib (depending on cartridge shoulder ) and box out ...then add the shim to the right side to make up the width . Relieve the magwell for the shift in the rear mag follower groove . |
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Youz guyz have been busy.... let's see if I can add some of my thoughts  - The 'composite' bullet (Al-Cu). OK, ya done it now. Got the wheels turning.  Broke out the design tools, working on something, will reach out to someone who likes to make this kind of stuff on his 5 axis machines and see what we can conjure up. Actually, two ideas. Fingers crossed.- Mags. So we had discussions at SHOT and we're hoping those will bear fruit. Thus far, no news, I will reach out to one of the parties, having already reached out to another. Had a crazy idea last night that I want to try and see if that works. This 3D printing might offer some relief, however, I have one example sitting here that did NOT work - at least, not for our high pressure SOCOM. As above, fingers crossed, I will post updates ASAP. - Brass. Thomas is a master at making tools so that he can create what is needed. We took 500 Jeffery brass and gave it .532" rims. It would not be that hard to take 338 RCM brass and give it .473" rims so you can use standard bolts. If I win the PowerBall, I will buy that Case Head Turning machine and start a small business modifying brass...  The SR high pressure brass for the SOCOM already exists (I refuse to call it by its name), I ran loads up to 60K and I have some printing from the extractor/ejector, but primers are OK. In the rifle shown, recoil was decidedly less than in my 9.3" lightweight AR15 in .458.... But that rifle is also no lightweight, I might get the barrel turned down...
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Be careful when the boss asks "Have you ever been to ...?"
"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
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Marty , I found a thing . I was thinking someone on here showed something similar some time back so I went a searching . Kaliber Tech KT10 AICS mag lower . 300wsm mag should do it and 10 rounders available. * 2.955" COAL - I have to say , that magwell looks quite chunky being set up for a single-stack. If one wanted to do a 416 slim rhino lapua Kurz with a .535 case rim ... Pretty nice set up . He goes over development and fine points. Its giving thoughts of a 375wsm .  Semi-auto 6.5 PRC/300 WSM | Kaliber Tech KT10 Longbow |
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Just as another aside that also happens to coincide with your 470 rhino , Marty. The 375 SwissP appears to be a rebated 500 Jeffrey case . Loaded ammo cheaper than a 500 Jeffrey case haha . I might have to pick me up a box of that just for the collection of odd cartridges. |
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OK, so we need a GLFA Long Action in 375 Swiss P.... But I am afraid we have strayed far from the actual topic of this post - the high pressure, extended range .458 SOCOM... One of the magazine discussions is progressing, so fingers crossed.... On the topic of magazines, all these discussions have made me try a number of other creative combinations and I will be trying at least one of those in the foreseeable future. If that is even partially successful, I will see if that then warrants progressing another project that BigBore is intimately familiar with... 
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Be careful when the boss asks "Have you ever been to ...?"
"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
"You got out once. You dip so much as a pinky back into this (ARFCOM) pond... you may well find something reaches out... and drags you back into its depths".
Joined:
Aug 2023
Posts:
9295
EE: 0% (0)
NC, USA
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