Converting a Marlin 1894 .32 H&R Mag to ..327 Fed. Mag

[trooper joe]

I have thought about this conversion for a very long time and have finally located a “donor” Marlin 1894 JM 32 H&R at a decent price (only 3 times the original MSRP).

However, I am now getting some information that the Marlin is rated at only 40,000 PSI and the .327 Fed Mag may be rated at 45,000 PSI.

Does anyone have any information on this?

I do have a Henry Brass .327 carbine that is actually built on a Marlin 336 type of action and probably rated for a higher pressure threshold than the Marlin 1894. So if the consensus is to stay away from that conversion, I will keep the Marlin as is for .32 H&R Mag. I can pair the Henry up with my Ruger single seven which is in .327 Fed.

Thanks for any info.

Trooper Joe

[trooper joe]

Here is what I am working with.




Trooper Joe

[Paladin]

I am not the SME on this but would sleeving the barrel allow the higher pressure?

[JFE]

A Marlin in 32 mag is quite rare and an expensive way to 327 Fed performance. If it were me I’d check the throating of your rifle as I suspect it will have a long throat (being a pistol cartridge). If so, I’d load the 32 mag to a longer OAL using a suitable bullet that fits your throat and cycles in your rifle. This is likely to be a cast bullet.

Having said that I’d just use a 357 mag rifle, which performs really well with powders like Lil’Gun.

[marlinman93]

Getting the action to cycle reliably with the longer cartridge will require reworking the carrier also. Can't just ream the chamber to .327 Federal.

[AJMD429]

.
I thought about that myself at one point, but decided just to buy a Henry lever action already chambered in 327 FedMag.

https://www.henryusa.com/rifles/henry-big-boy-steel/



As soon as I can get a decent quantity of BRASS for it, I'll start working up a load...

[Scott Tschirhart]

I have a Marlin that has been converted and I paid about what you would pay for any other Marlin 94 these days.

Feeds .32 Long, .32 H&R Mag and.327 Federal interchangeably.

[AJMD429]

.
I'd be concerned about the pressures if the gun isn't "designed" for it, although my MAIN reason for wanting a levergun in 327 Fed was in case I got a revolver in the same round, and the brass seems sturdier than 32-20. I just didn't think I'd ever pony up for a custom 32-20 Ruger SP101 or GP101, but I've seen them in 327 Fed. I don't think I'd bother 'hot' loading the cartridge anyway though - if I want THAT I'll just grab a 357 Mag - I've got leverguns and wheelguns that match in that fine cartridge, but the "32" cartridges just aren't that popular these days, so the choice is limited...

[Scott Tschirhart]

Photos of mine.

[Scott Tschirhart]

I’m not concerned in the least about this gun or shooting the hottest .327 ammo in it.

I’ve seen how this action takes smoking hot .357 and .44 Magnum without any difficulty and the.327 has a smaller head than those catridges.

[trooper joe]

Scott,

Grizzly must have changed his mind. Here is the email he sent me when I asked him about converting a Marlkn .32 H&R Mag.:

From: Lew Bonitz <lew@grizzlycustom.com>
Date: December 30, 2024 at 5:17:45 PM EST
To: xxx….x@comcast.net
Subject: .327 Mag Custom Marlin


Joe,

Thank you for the inquiry!

The first thing that comes to mind is the additional 10,000psi that the .327 generates over the .357. 45,000psi in the Marlin 1894 seems like a lot to me.

Sincerely,

Lew Bonitz
Grizzly Custom Guns, LLC
325 Patterson Ranch Lane
Columbia Falls, Montana 59912
www.GrizzlyCustom.com
406.892.4570

I am going to try and get ahold of him again.

Trooper Joe

[Scott Tschirhart]

Trooper,

That’s four different gunsmiths that have told you that this is a bad idea, including the one who did mine.

Probably best to abandon this project. Use the Henry for .327.

[fourbore]

I think it is a bad idea simply because it is un necessary. A person can easily purchase, trim and handload 327 brass to shoot in the Marlin and any 327 handgun. It is no different than shooting 38 special in a 357 which almost everybody does. And 38 special can be loaded very +P, if desired.

If I were to buy a 327 reamer and modify one of those wonderful Marlins, I sure not be stamping anything on the barrel. It would be my little secret. I do own and shoot 32 H&R and 327. No problem dealing with two versions.

[trooper joe]

Trooper,

That’s four different gunsmiths that have told you that this is a bad idea, including the one who did mine.

Probably best to abandon this project. Use the Henry for .327.

Scott,

I think you are right especially since I almost had to max out my home equity loan to buy it .

Trooper Joe