P14 DG rifles

[HWL]

@Ray B
Either way both were faster than the mausers.
SMLE 10 rounds then reload
Garand 8 rounds
Mauser 5 rounds
Bob

Not sure for that.....

Mauser M98 with 20 rounds Grabenmagazin (trench magazine)

HWL

 

[VSOHunt]

@VSOHunt Roy Dunlap's book 'Gunsmithing' is worth reading on this subject. He went to a great deal of trouble to detail the right and wrong--unsafe--ways to modify the breech-bolts on these rifles.

Thank you. I will look into that. Much appreciated

 

[Hagler.450Ex]

I used a Cogswell & Harrison .404 Jeffery (which was built on a Pattern 14 Enfield action) to hunt a hippopotamus bull on land.
View attachment 758502View attachment 758504
At one time, even Holland & Holland (from 1918-1957) offered magazine rifles built upon the Pattern 14 Enfield action.
View attachment 758503
These were very strong Magnum length actions, thoroughly to be relied upon. They can be used to build rifles as large as the .505 Gibbs without a problem.

I need one exactly like that in .505 Gibbs.

 

[Hunter-Habib]

I need one exactly like that in .505 Gibbs.

So do I ! With a 24" Douglas Premium Hexagonal barrel, a Turkish walnut stock, wide V backsights, uncovered ivory bead foresight, extended drop belly magazine (4+1 magazine capacity) and a long throat for accommodating 600Gr bullets.

 

[Hagler.450Ex]

So do I ! With a 24" Douglas Premium Hexagonal barrel, a Turkish walnut stock, wide V backsights, uncovered ivory bead foresight, extended drop belly magazine (4+1 magazine capacity) and a long throat for accommodating 600Gr bullets.

The perfect rifle to have in hand when things get hot. I'd be willing to settle for nothing fancy, but agree completely about the sights and magazine capacity. As long as it cycles good and chunks that brass out when the dust is flying. I'm on the lookout now, even a barreled action if I can find one. I was almost convinced of going with a .500 Jeffery on a standard Mauser action, but I like this much better.

 

[Ontario Hunter]

As I said, I have all three WWI Western Front military bolt actions on hand: 98 Mauser, 1903 Springfield, and P14 Enfield (essentially the same as 1917 Enfield). The Enfield is the only one still in its military configuration. Of the three, the Springfield is clearly the smoothest and easiest to cycle. It almost closes itself. The Mauser with safety in position two (safety engaged but bolt free to cycle) is slightly smoother but the gun would never be cycled that way for followup shots. Both the Enfield and Springfield have 2-position safeties (the latter modified for scope relief). The Enfield is by far the poorest cycling. Besides awkward to cock on closing, the rifle is less than smooth when opening. It hangs up slightly before the lugs are clear of the locking ring, even with an empty magazine (but only when bolt is being opened after gun is fired). As far as I know the modifications to the actions of my sporterized Mauser and Springfield would not significantly improve smoothness of operation: 1) beveling the end of the follower so it does not lock the bolt open on an empty magazine, 2) polishing off the bluing on bolt, and 3) replacing military triggers with Timneys. P14 Enfield followers were not designed to block the bolt open on empty magazine. The Mauser's 8mm feeding rails were modified to cycle 404J but as far as I can tell that did not change cycling smoothness. Neither did adding Timney triggers. For me, the most important qualities of a dangerous game bolt rifle are smoothness and reliability during cycling. I don't want to be fighting the gun to work the bolt and, of course, I need to be sure the gun will always work when things get exciting. For reliability I prefer standard length action with shorter bolt throw ( = less risk of short stroking and jamming). This pretty much limits me to 416 Rigby maximum which in my opinion is more than enough gun to efficiently kill any mammal that walks the planet. Also, 3+1 is plenty of ammunition in a dangerous game rifle. Between them, the hunter and PH would have six to nine rounds in play without reloading (depending on design of PH's rifle) and that should be enough to do the job if they're reasonably close to doing their jobs. Unless they are totally incompetent or their buffalo just jumped out of a phone booth wearing a cape, six to nine shots fired in rapid succession from 375 or greater should put him away. I think it would be a rare affair when hunter and PH did not have an opportunity to reload in a wounded animal shitshow. 4+1 is just extra weight in hand ... which admittedly may not necessarily be a bad thing for thumper guns.

For a lot of reasons P14 would not be my first choice for a dangerous game rifle project. It might be my last choice. Mausers are by far the easiest to find aftermarket parts. Springfield probably the most difficult. And that factor may or may not be a consideration. If one can afford the money and the time involved in having a gunsmith (or rather gunmaker) fabricate everything (and that does require a LOT of $$$ and years of waiting) then maybe it's not an important consideration. I built my 404 on 98 Mauser in four months for less than $3K. That was in 2023. If I'd ordered it from a gunsmith, I'd be lucky to not still be waiting for it to be finished. And finally, the Enfield is the most difficult to make into a civilized rifle. There's the damned sight ears on the receiver that have to be removed and the duck pond cavity between them that must be filled in. Cock on closing, guppy belly magazine/stock, and dog leg bolt handle may or may not be removed/modified.

 

[JG26Irish_2]

I did not build it but do have a P14 Enfield in 375HH built by ER Shaw in Penn. It has the Shaw bbl and is modified to cock on opening. I have enjoyed this thread as I always wanted to understand better how that mod was done. Mine is one of the most accurate rifles I own and I really enjoy hunting with it. I have taken it to Africa where I took a Buffalo and a Kudu with it. I have mine topped with a 1-6x Kahles K16i which is a superb optic for close range hunting while still being clear enough to ethically take longer shots out to the limit of the cartridge. These are great rifles and the action is built like a bank vault.

 

[Ontario Hunter]

I did not build it but do have a P14 Enfield in 375HH built by ER Shaw in Penn. It has the Shaw bbl and is modified to cock on opening. I have enjoyed this thread as I always wanted to understand better how that mod was done. Mine is one of the most accurate rifles I own and I really enjoy hunting with it. I have taken it to Africa where I took a Buffalo and a Kudu with it. I have mine topped with a 1-6x Kahles K16i which is a superb optic for close range hunting while still being clear enough to ethically take longer shots out to the limit of the cartridge. These are great rifles and the action is built like a bank vault.

View attachment 759328

Very nicely done! Did he retain the military floor plate? I don't see a latch for hinged one. Which is fine by me. My 404's bottom metal with hinged floorplate came from Blackburn. When modifying the feeding rails it was handy being able to repeatedly open the floor plate and temporarily drop the follower out of the way vs pulling the entire guts from the gun. Other than that I don't believe I have ever opened the floorplate. Oh wait ... a couple of times I tried loading the magazine from the bottom. Did not work! Causes a jam half the time if cartridges are not stacked just right. What bases and rings? Those rings are heavy duty! I presume with guppy belly removed it is 3+1? I am entertaining thoughts of building something with the P14 that my late wife's grandfather mangled. It has no collectable value so why not. Your rifle is a perfect model. Might even go with 375 caliber though I need two DGRs like I need a hole in the head.

 

[JG26Irish_2]

Very nicely done! Did he retain the military floor plate? I don't see a latch for hinged one. Which is fine by me. My 404's bottom metal with hinged floorplate came from Blackburn. When modifying the feeding rails it was handy being able to repeatedly open the floor plate and temporarily drop the follower out of the way vs pulling the entire guts from the gun. Other than that I don't believe I have ever opened the floorplate. Oh wait ... a couple of times I tried loading the magazine from the bottom. Did not work! Causes a jam half the time if cartridges are not stacked just right. What bases and rings? Those rings are heavy duty! I presume with guppy belly removed it is 3+1? I am entertaining thoughts of building something with the P14 that my late wife's grandfather mangled. It has no collectable value so why not. Your rifle is a perfect model. Might even go with 375 caliber though I need two DGRs like I need a hole in the head.

The floor plate is held in place with a pin and screw so it cannot fall out while hunting, so no hinge. I cannot say where it came from. It is a 4+1 mag with 375HH loads. Rings are Leupold if I recall correctly. 30mm. You need a new rifle for each new hunt in my opinion, maybe two?, lol

 

[roklok]

Don't judge all P14/1917 actions by one example. I agree, the cock on closing in military configuration does not work for me, however I have 1917s that are extremely slick operating, better than my Mausers. I have fourteen P14/1917/Rem 30 actions here between project rifles, bare actions, complete actions, and finished rifles. Some do work rather roughly due to cock on close, age, corrosion, gummed up lubrication, etc. However the ones that are complete rifles and currently in use are extremely slick. These actions have much less bolt wobble than Mausers, and are very slick operating. I like Mausers too, don't get me wrong, but the Enfields are slicker when set up as cock on open. I have Mauser 98s in 7x57, 30-06, .375 H&H, 458 WM, and I prefer the Enfield style actions.

Aftermarket parts are indeed harder to find and/or non existent as compared to Mausers, valid concern. However a competent builder can make a first class DG rifle from these actions. Not all of them have the "duck pond" on rear receiver ring, Remingtons and some Eddystones do not. Winchesters and some Eddystones do have the "duck pond." A big plus to using these actions for builds is the bolt handle and safety are good to go for low scope mounting, unlike the military Mausers. The dog leg bolt handle is a cosmetic issue some do not like, not a functional one, and can be changed easily. The Enfield actions are definitely better suited for magnum length cartridges with less "shoehorning" required than the M98. As far as the receiver ears, I would not cut ears off a non-modified receiver. There is a glut of these actions that were already modified in the 30s, 40s, and 50s during the heyday of the sporterization era that I would not consider cutting an unmodified receiver. There are so many that are already cut that this is a non-factor in my opinion. I just counted 44 1917s currently listed on Gunbroker that already have the receiver ears cut off in sporterized condition. A non-factor, cut receivers are more than plentiful.

One other important point when building a DG rifle with these, use a coil spring ejector ! The weak point of these actions is the leaf style ejector spring that are prone to breakage. Remington changed these to a coil spring setup in their Model 30, and it is easy and inexpensive to change to a coil spring ejector on the military actions.

 

[Bob Nelson 35Whelen]

As I said, I have all three WWI Western Front military bolt actions on hand: 98 Mauser, 1903 Springfield, and P14 Enfield (essentially the same as 1917 Enfield). The Enfield is the only one still in its military configuration. Of the three, the Springfield is clearly the smoothest and easiest to cycle. It almost closes itself. The Mauser with safety in position two (safety engaged but bolt free to cycle) is slightly smoother but the gun would never be cycled that way for followup shots. Both the Enfield and Springfield have 2-position safeties (the latter modified for scope relief). The Enfield is by far the poorest cycling. Besides awkward to cock on closing, the rifle is less than smooth when opening. It hangs up slightly before the lugs are clear of the locking ring, even with an empty magazine (but only when bolt is being opened after gun is fired). As far as I know the modifications to the actions of my sporterized Mauser and Springfield would not significantly improve smoothness of operation: 1) beveling the end of the follower so it does not lock the bolt open on an empty magazine, 2) polishing off the bluing on bolt, and 3) replacing military triggers with Timneys. P14 Enfield followers were not designed to block the bolt open on empty magazine. The Mauser's 8mm feeding rails were modified to cycle 404J but as far as I can tell that did not change cycling smoothness. Neither did adding Timney triggers. For me, the most important qualities of a dangerous game bolt rifle are smoothness and reliability during cycling. I don't want to be fighting the gun to work the bolt and, of course, I need to be sure the gun will always work when things get exciting. For reliability I prefer standard length action with shorter bolt throw ( = less risk of short stroking and jamming). This pretty much limits me to 416 Rigby maximum which in my opinion is more than enough gun to efficiently kill any mammal that walks the planet. Also, 3+1 is plenty of ammunition in a dangerous game rifle. Between them, the hunter and PH would have six to nine rounds in play without reloading (depending on design of PH's rifle) and that should be enough to do the job if they're reasonably close to doing their jobs. Unless they are totally incompetent or their buffalo just jumped out of a phone booth wearing a cape, six to nine shots fired in rapid succession from 375 or greater should put him away. I think it would be a rare affair when hunter and PH did not have an opportunity to reload in a wounded animal shitshow. 4+1 is just extra weight in hand ... which admittedly may not necessarily be a bad thing for thumper guns.

For a lot of reasons P14 would not be my first choice for a dangerous game rifle project. It might be my last choice. Mausers are by far the easiest to find aftermarket parts. Springfield probably the most difficult. And that factor may or may not be a consideration. If one can afford the money and the time involved in having a gunsmith (or rather gunmaker) fabricate everything (and that does require a LOT of $$$ and years of waiting) then maybe it's not an important consideration. I built my 404 on 98 Mauser in four months for less than $3K. That was in 2023. If I'd ordered it from a gunsmith, I'd be lucky to not still be waiting for it to be finished. And finally, the Enfield is the most difficult to make into a civilized rifle. There's the damned sight ears on the receiver that have to be removed and the duck pond cavity between them that must be filled in. Cock on closing, guppy belly magazine/stock, and dog leg bolt handle may or may not be removed/modified.

@Ontario Hunter
Sorry to inform you but the P14 unless the mag follower is beveled was designed to lock open on the last round being fired to allow a soldier to recharge the mag.
My P14 holds the bolt open on the last shot so does my M17 in 35 Whelen AI.
Bob

 

[Bob Nelson 35Whelen]

I did not build it but do have a P14 Enfield in 375HH built by ER Shaw in Penn. It has the Shaw bbl and is modified to cock on opening. I have enjoyed this thread as I always wanted to understand better how that mod was done. Mine is one of the most accurate rifles I own and I really enjoy hunting with it. I have taken it to Africa where I took a Buffalo and a Kudu with it. I have mine topped with a 1-6x Kahles K16i which is a superb optic for close range hunting while still being clear enough to ethically take longer shots out to the limit of the cartridge. These are great rifles and the action is built like a bank vault.

View attachment 759328

@JG26Irish_2
If you compare the locking lugs on a Mauser with the ones on Enfield you will find a big difference.
The lugs on a Mauser are square and lock up in square recesses.

The lugs on an Enfield a what some call helical, they are not square and when the lock up they go into the actin and lock up like a bank vault.
Don't believe me Chevy it for yourself.

Bob

 

[Ontario Hunter]

Don't judge all P14/1917 actions by one example. I agree, the cock on closing in military configuration does not work for me, however I have 1917s that are extremely slick operating, better than my Mausers. I have fourteen P14/1917/Rem 30 actions here between project rifles, bare actions, complete actions, and finished rifles. Some do work rather roughly due to cock on close, age, corrosion, gummed up lubrication, etc. However the ones that are complete rifles and currently in use are extremely slick. These actions have much less bolt wobble than Mausers, and are very slick operating. I like Mausers too, don't get me wrong, but the Enfields are slicker when set up as cock on open. I have Mauser 98s in 7x57, 30-06, .375 H&H, 458 WM, and I prefer the Enfield style actions.

Aftermarket parts are indeed harder to find and/or non existent as compared to Mausers, valid concern. However a competent builder can make a first class DG rifle from these actions. Not all of them have the "duck pond" on rear receiver ring, Remingtons and some Eddystones do not. Winchesters and some Eddystones do have the "duck pond." A big plus to using these actions for builds is the bolt handle and safety are good to go for low scope mounting, unlike the military Mausers. The dog leg bolt handle is a cosmetic issue some do not like, not a functional one, and can be changed easily. The Enfield actions are definitely better suited for magnum length cartridges with less "shoehorning" required than the M98. As far as the receiver ears, I would not cut ears off a non-modified receiver. There is a glut of these actions that were already modified in the 30s, 40s, and 50s during the heyday of the sporterization era that I would not consider cutting an unmodified receiver. There are so many that are already cut that this is a non-factor in my opinion. I just counted 44 1917s currently listed on Gunbroker that already have the receiver ears cut off in sporterized condition. A non-factor, cut receivers are more than plentiful.

One other important point when building a DG rifle with these, use a coil spring ejector ! The weak point of these actions is the leaf style ejector spring that are prone to breakage. Remington changed these to a coil spring setup in their Model 30, and it is easy and inexpensive to change to a coil spring ejector on the military actions.

I thought all the P14s made on both sides of the Atlantic had the duck pond cavity between the ears. Grandpa drilled some holes in the right ear to makeshift mount a scope to this rifle. Sad thing is he butchered a military scope to make it fit. That scope would probably be worth more than the rifle if he'd left it alone. So I may as well trim the ears since the gun cannot be restored. It could very well be the case that this one is dirty which may account for it sticking during opening after firing. Odd timing though. It opens just fine when striker is cocked.

I think I'll keep my eye open for a bolt that cocks on opening. They come up from time to time. You're right, the action is significantly longer than 98 Mauser. 375 would be a nice project. Good to know about ejector spring issues. Maybe I could fill the duck pond with a fine piece of wood? Birdseye maple? As I recall the mag box is separate from bottom metal? That would make modifying magazine a lot easier. I have been told those barrels are a pain to peel from receiver. Even for a military rifle. Don't find this P14 safety particularly pleasant to operate but I'm thinking it might be worn out or full of crud. My 404 Mauser has 3-position Model 70 safety which is pretty hard to beat. Been looking for a post-64 real Winchester Model 70 bolt shroud for my 30-06. Wisner says they will thread onto 1903 Springfield. Of course it will require fabricating a striker but I see lots of military surplus strikers available to play with. I can certainly live with the dog leg bolt. A signature feature. I cut the knob of my Springfield to access a left side scope safety. A lot of guys have tried to correct me: "That's a Mauser not a Springfield". Then I point them to bolt release.

 

[Bob Nelson 35Whelen]

I thought all the P14s made on both sides of the Atlantic had the duck pond cavity between the ears. Grandpa drilled some holes in the right ear to makeshift mount a scope to this rifle. Sad thing is he butchered a military scope to make it fit. That scope would probably be worth more than the rifle if he'd left it alone. So I may as well trim the ears since the gun cannot be restored. It could very well be the case that this one is dirty which may account for it sticking during opening after firing. Odd timing though. It opens just fine when striker is cocked.

I think I'll keep my eye open for a bolt that cocks on opening. They come up from time to time. You're right, the action is significantly longer than 98 Mauser. 375 would be a nice project. Good to know about ejector spring issues. Maybe I could fill the duck pond with a fine piece of wood? Birdseye maple? As I recall the mag box is separate from bottom metal? That would make modifying magazine a lot easier. I have been told those barrels are a pain to peel from receiver. Even for a military rifle. Don't find this P14 safety particularly pleasant to operate but I'm thinking it might be worn out or full of crud. My 404 Mauser has 3-position Model 70 safety which is pretty hard to beat. Been looking for a post-64 real Winchester Model 70 bolt shroud for my 30-06. Wisner says they will thread onto 1903 Springfield. Of course it will require fabricating a striker but I see lots of military surplus strikers available to play with. I can certainly live with the dog leg bolt. A signature feature. I cut the knob of my Springfield to access a left side scope safety. A lot of guys have tried to correct me: "That's a Mauser not a Springfield". Then I point them to bolt release.

@Ontario Hunter
To the best of my knowledge all P14s were made in the USA. The English were unable to produce enough P13s in 280 so sent it to the USA to be made. WW1 started so they scrapped the 280 and just had it chambered in 303 and it was called the P14. When production of the SMLE was sufficient they cancelled the contact then the USA entered the war. Finding themselves with not enough 03 Springfields the got the P14 and converted it to 30-06 and it became the M17.
After the great war Remington had a heap of parts left over and the Remington Model 30 and 30S was born.
All this from the humble beginnings of the P13S
Bob

 

[Ontario Hunter]

Bob
You are correct. Grandpa Bert beveled the end of the follower just enough to allow bolt to close on empty magazine. It was my understanding that P14 was being made both in Britain and US. Looks like I understood wrong. When the US entered the war the US didn't have enough Springfield rifles so the plants making P14 simply made a few modifications to set machinery to turn out Enfields in 30-06. Presto they became 1917 Enfield rifles. This one is stamped ERA on top of locking ring. Is that Eddystone?

Edit: Yep. ERA = Eddystone Remington Arms

 

[Grumpy gumpy]

It could just be me (and the rest of the world) but every time someone says "Enfield " my brain automatically thinks SMLE (Short Magazine Lee Enfield), then sideshifts to P53 and freezes. It could be because the P14, M17 and 03 Springfield are all Mauser based in themselves (hence why the Us got sued after the war and lost) so I lump them all as variants . It is confusing at times.
And I’m with roklok with his description on function
Gumpy

 

[Robmill70]

My old P-14 in 375HH

 

[mgstucson]

This is a great thread and I have enjoyed all the input and knowledge shared freely by so many here. As an old military rifle buff, among other things i could be called, I have SMLE, 96 mauser, 98 mauser, p17, Arisaka Type 38, and 1903 rifles. In straight up military configuration, the 96 is most accurate. Cover 4 shots with a quarter at 100yds all day WITH IRON SIGHTS (back when I could see well enough to use them.) All of them can be made accurate of course. The Arisaka may be the strongest action, followed by the p17's.

The SMLE's with their 10 shot mags, short bolt throw, cock on closing, bolt/trigger geometry and tapered case are no doubt the fastest bolt actions to 10 shots. The SMLE's were maybe the least accurate but as far as laying down battlefield accurate fields of fire in short order, they are hard to beat. The 303 cartridge, like current 7.62x39, were also known for battlefield reliability in all sorts of adverse conditions. I think the case taper on both has a lot to do with that. Especially in situations where barrels became blazing hot after hundreds of rounds fired in less than an hour. A lot of that isn't particularly applicable to sporting applications, but it sure made the UK hell on wheels in the WW's until the automatic battle rifles took over.

My latest purchase, (impulse lunch-hour-at-pawn-shop buy) is a mostly military, sort of refinished, slightly sporterized P17. It still has the dog ears and military sights. I bought it to build a DG rifle on. I have everything I need up to 458 Lott covered rifle wise, so I am thinking a 500 of some type. I have looked into 500 Jefferey, 505 Gibbs, and the 500 A Square among others. I am sort of leaning hard toward a 500 A-Square, since they were originally built on this action anyway. (I kind of like the historical accuracy of it. It is also why I like my Whelen's on '03 actions.) Although proper headstamped 500 A-Square cases are hard to come by, 460 Weatherby donor cases are cheaper and easier to find than ANY OTHER 500 case. I make my own 510 caliber bullets, so brass availability is my only real supply chain concern. I only need 100 or so headstamped cases, as I can use 460 wthby cases otherwise.

Anybody have a gunsmith you like for this kind of build?

 

[Josh P]

My latest purchase, (impulse lunch-hour-at-pawn-shop buy) is a mostly military, sort of refinished, slightly sporterized P17. It still has the dog ears and military sights. I bought it to build a DG rifle on. I have everything I need up to 458 Lott covered rifle wise, so I am thinking a 500 of some type. I have looked into 500 Jefferey, 505 Gibbs, and the 500 A Square among others. I am sort of leaning hard toward a 500 A-Square, since they were originally built on this action anyway. (I kind of like the historical accuracy of it. It is also why I like my Whelen's on '03 actions.) Although proper headstamped 500 A-Square cases are hard to come by, 460 Weatherby donor cases are cheaper and easier to find than ANY OTHER 500 case. I make my own 510 caliber bullets, so brass availability is my only real supply chain concern. I only need 100 or so headstamped cases, as I can use 460 wthby cases otherwise.

Anybody have a gunsmith you like for this kind of build?

I’ve been keeping an eye out for a Remington/Winchester M1917 action that hasn’t been run through a dull bandsaw. I can’t think of a better action for a 505 Gibbs build that’s actually obtainable, and I’ve seen some sporters that were absolutely beautiful.

If anyone has any resources (print or video) for the conversion process of M1917 actions to .50+ caliber, it wouldn’t hurt my feelings to hear about them.

 

[Daryl S]

This is a great thread and I have enjoyed all the input and knowledge shared freely by so many here. As an old military rifle buff, among other things i could be called, I have SMLE, 96 mauser, 98 mauser, p17, Arisaka Type 38, and 1903 rifles. In straight up military configuration, the 96 is most accurate. Cover 4 shots with a quarter at 100yds all day WITH IRON SIGHTS (back when I could see well enough to use them.) All of them can be made accurate of course. The Arisaka may be the strongest action, followed by the p17's.

The SMLE's with their 10 shot mags, short bolt throw, cock on closing, bolt/trigger geometry and tapered case are no doubt the fastest bolt actions to 10 shots. The SMLE's were maybe the least accurate but as far as laying down battlefield accurate fields of fire in short order, they are hard to beat. The 303 cartridge, like current 7.62x39, were also known for battlefield reliability in all sorts of adverse conditions. I think the case taper on both has a lot to do with that. Especially in situations where barrels became blazing hot after hundreds of rounds fired in less than an hour. A lot of that isn't particularly applicable to sporting applications, but it sure made the UK hell on wheels in the WW's until the automatic battle rifles took over.

My latest purchase, (impulse lunch-hour-at-pawn-shop buy) is a mostly military, sort of refinished, slightly sporterized P17. It still has the dog ears and military sights. I bought it to build a DG rifle on. I have everything I need up to 458 Lott covered rifle wise, so I am thinking a 500 of some type. I have looked into 500 Jefferey, 505 Gibbs, and the 500 A Square among others. I am sort of leaning hard toward a 500 A-Square, since they were originally built on this action anyway. (I kind of like the historical accuracy of it. It is also why I like my Whelen's on '03 actions.) Although proper headstamped 500 A-Square cases are hard to come by, 460 Weatherby donor cases are cheaper and easier to find than ANY OTHER 500 case. I make my own 510 caliber bullets, so brass availability is my only real supply chain concern. I only need 100 or so headstamped cases, as I can use 460 wthby cases otherwise.

Anybody have a gunsmith you like for this kind of build?

Back in the 70's, I fired a shot from a BRNO the fellow had turned into a (virtual) .505 Barnes Supreme, shooting 600gr. Old Style Barnes copper and lead 600gr. RN's. Been a long tine since then, but his load, AFAIK, was 125gr. of 3031. I know it wasn't H4831. Pretty sure that was on the box. Don't load that without, we'll, you know.
The case was none other than the .378 WTBY, or .460.
It spun me around like a weathercock. Didn't expect that. I was a 185 pound strong man, back then.
I think that round would be a good choice, if up to it.
He said the vel. was 2,600fps.