7mm x 54 Rimmed Russian in a Handi

[anweis]

It may sound crazy, and it may very well be expensive, but i was thinking about a Handi rifle chambered for the Russian Rimmed case and shooting 7 mm bullets.
Why? Because i believe that rimmed cases work much better in that type of action, extracting better. And because such a cartridge will probably exceed 7-08 performance, most probably it will be in the .280 range.  
The big question is: is it possible to rechamber a 7-08 Handi Rifle to take that Russian case? If not possible due to dimenssions, how about the .303 British case with the same 7mm bullets?
I guess that if the chamber and throat  were to be recut properly, and a few lapping bullets were to be fired, the final product should be a flat shooting and accurate rifle.
Do you think that there would be pressure and safety problems for the rifle? I don't think that this cartridge would generate more pressure than a hot loaded .280 or 30-06. I know that there should not be any problem with the cartridge, because Soviets and Finns had variants of the 54 Rimmed case necked down to 6.5 mm and it worked great (in bolt action rifles). Also, the .303 British case has been necked up and down in the past with good results. I would prefer the Russian case, though...for sentimental reasons.
I wonder how much it would cost though....Any idea how much would the whole conversion cost?
Shoot safe.

[Fred M]

Anwise.
This is not to say it can't be done, but two things I feel are against it.

The rim is .567" even larger than a magnum case, it would substantially increase the thrust against the standing breech even with normal loads.

The ejector would need extensive remodeling. I would not consider it on a Handi. Whats wrong with the 280 Rem, notwithstanding nostalgia? Fred M.

[JPH45]

Not to start big arguements, the diameter of the case body at the head of the 7.62x54R is .485, as compared to a nominal diameter of .471 give or take a few thousandths for the -06 family case. (actually the 8mm Mauser, but that is another disscussion) The 7.62x54R operates at app 45,200 psi (at least according to Accurate Arms who used Norma ammo to determine pressures as no SAAMI standard for this round exists) and it is standard practice to never push a case above the pressure limits it was designed for. The 7-08 operates at 52,000 cup (its parent , the 308 operates at 62,000 psi), but the 7-08 drives 150 grain bullets to 2600-2700 fps the 7.62x54R drives them to 2500-2600 fps. I doubt that such a conversion would be worth the effort esspecially as you are dealing with a bastard case. I also don't think that extraction would be any more reliable. One fellow went so far as to have his 308 rechambered to the 308X444, which is basically a rimmed 308 based on the 444 Marlin case, unfortunately, it did not solve his troubles.

I would stay with the 7-08, since you handload it sould be a simple task to load ammo that won't stick. As well, you would stay with a case for which there is a ready supply of brass, and can be readily formed from several other cases if the need existed.

As Fred said, if you want 280 performance, get one and be done with the headaches.

[anweis]

Thank you for replies gentlemen. I will not do a wildcat just for the the vanity of wildcatting. It looks like i won't gain much, so i will stay with my friends, the 6.5 Swede, the .280 and the 7-08. I wasn't looking for a new cartridge necessarily. And yes, these three cartridges will put down a chamois or an antelope from across the valley like there is no tomorrow.

[Leftoverdj]

Fred, I gently disagree. The rim is irrelevant to the case head thrust.  What does matter is the interior diameter of the cartridge. That's what the gas pressure has to push against.  There is only maybe .015 difference in that area.

I can see someone with a huge hoard of 7.62x54R ammo rechambering a .308 Win Handy to the Russian cartridge. Given the Handi's generous groove diameter and the lower pressures of the Russian, it would be safe enough. I can't see basing a new wildcat on that round, though.

[Mitch in MI]

I'm with DJ here. You could rechamber a 7-08 to a 7x54R, but about all you'd gain is a rim.
It's possible that you could get away with using the ejector from a 45-70 on the 54R case, but you might get a better fit by grinding on a 30-30 ejector. Powder capacity would be about 1cc less than a 280rem. Even if you chambered it to 7mm-70 Government you'd lose some powder capacity to the 280, not to mention four inches of barrel length.
If you're dead set on having a rimmed 7mm, I'd cut a 30-30 rim on the 7-08 and call it a 7mm-307. H&R already makes an ejector to fit that rim.

[Leftoverdj]

Mitch, you got my brain cells firing. It would be fairly simple to cut a rim on a .280 and reform 7x65R brass to create a .280R.  'Course the brass would cost at least a buck a case, but you would have a rim.

[marv]

They made a 7x 64 handi   America outdoor store in OK city Ok
 had 3 in the soring 93 Marv.

[kjeff50cal]

Gentlemen/women, I think you are talking about at least two different cartriages with at least two different bore sizes. The Russian caliber 7.62 X 54R has a bore dia. of between .310" to .318" (depending on which Mosin Nagant you have). There is however a rimmed version  of the classic 7mm Mauser named 7 X 57R which has a groove dia. of .280".  I do not want to hear of anyone wrecking a handirifle because of an incorect bore size :shock: .

[JPH45]

Off the to of my head, (so don't be judge me too harshly) I don't think there would be a lot of difference between the 7x57R and the 7mmx444 (7mm JDJ?) I also think there is a rimmed version of the 9.3x62 which necked down should actually have just a bit more capacity than the 280, but I'm not sure the small gain would actually translate to much in velocity, and I'm not now convinced that a rim is any guarantee of extraction/ejection. I get stuck cases in my 30-30 after firing full juice loads in a case 2 times. This could be a result of the softness of the brass as much as any other cause. Do note that this is when neck sizing only and not full length sizing.

After keeping track of disscussions like this for well over a year, I have begun to think that sticking brass is a combination of several factors with few sure fire single approach solutions.

Kjeff50cal, anweis the original poster was in fact speaking of necking the 7.62 x 54R down to 7mm. Interesting though that you speak of the 7 x 57R, which given the good 'ol AI treatment could perform just as anweis was thinking.

[Fred M]

Leftoverdj.
I guess I did not look close enough at this cartridge. The Ruskies got their cake and eat it too. The rim has a bevel which is even further in than the case diameter of .485. So there is only as much thrust as the cartridge produces times the area of contact. That is a pretty clever design. A fellow could do that with other rimmed cases like the 307Win. But why bother when you have a 308. Fred M.

[lik2hunt]

Is the 7x54R the same as a 7x64Brenneke? If so then marv is right, there is ONE at Outdoor America Store in OKC, OK.

[anweis]

My main reason for thinking about the 54 R (Rimmed Russian) case necked down to 7 mm and in a Handi rifle was avoiding extraction problems. It looks like full sizing of the cases, cleaning of the extractor parts, and a chamber polish would solve that. After all, rimless cases are used in many expensive single shots, without extraction problems.
I am definitely not interested in spending my $$$ on wildcatting, we have more cartridges than we need.

[Mitch in MI]

When it works, an ejector can be nice if you need a quick follow-up shot. However, a cam powered ejector is a lot more positive.
I doubt we could convince H&R 1871 to change over to an ejector that used the force of the opening barrel to shove the brass out, but I can wish.

[naedlaen]

If the point is to go to a rim, why not cut the 307 Winchester rim on the 7-08 and use the 307 brass to form a 7-08 rimmed.  You could use either original brass or the 307 brass if you did not modify the ejector, but could modify the ejector to be more like a rimmed ejector if you stayed with the 307 brass.  Or form the 444 Marlin brass to the 7-08 chamber by running it into a 308 die first.

The 303 British is smaller in diameter, IIRC.  Check it out at www.reloadbench.com

Neal

[Leftoverdj]

Leftoverdj.
I guess I did not look close enough at this cartridge. The Ruskies got their cake and eat it too. The rim has a bevel which is even further in than the case diameter of .485. So there is only as much thrust as the cartridge produces times the area of contact. That is a pretty clever design. A fellow could do that with other rimmed cases like the 307Win. But why bother when you have a 308. Fred M.

Repeat after me, Fred, "The rim has absolutely nothing to do with case head thrust."

Whether the case is rimmed or rebated, head thrust is a function of the internal area at the base of the cartridge and the pressure at which the cartridge operates less any clinging effect of the sidewalls.  That's the area that the gas pressure has to work on.

[Fred M]

Leftoverdj.
Sorry I do not agree for various reasons. Case head pressure is well documented, by bolts completely stuck or very sticky. The bevel on that old Russian cartridge head is not a make work project, but a design to reduce bolt head thrust on these old rifles. If there was no case head thrust  why would you have a standing breech or a bolt for that matter. Loose the lugs on a bolt and it will perforate your head if nothing else would stop it.
Weatherby installs 9 locking lugs is that just for show? Or is it to restrain 70Kpsi in all directions? Ok I am off fishing for two weeks.
Fred M.

[jbtazgrabber]

how about the 30 40 krag    about 10 years ago i had a 30 30 rechamber for a 3040 krag it worked real well then they built a stronger action and now look what we have   now