? Ruger SP101 .32 H&R Mag

[warren5421]

I own a SP101 .32 H&R Mag, would it be worthwhile to ream it to .327 Mag?

[Mk42gunner]

I wouldn't. For a few reasons: 1. The .32 H&R does what I need a small caliber revolver to do. and 2. Are you absolutely sure the reamer will clean up the chambers? No matter what the specs say, there is always a chance you will end up with a stepped chamber. 3. Loss of resale do to modifications. and finally 4. Is the cylinder long enough?

It is your gun, not mine. If you plan to keep it forever, that is one thing, but if you ever need to sell it....

Look at all the custom rifles in wildcat calibers that can hardly be given away.

Robert

[megasupermagnum]

It can be done, it works great. Ahlmans gunsmithing in Morristown, MN does a real good job with them.

I don't think it is really worth it now though like it was 10 years ago. SP101's in 327 Federal are just so plentiful now, I'm not sure I'd bother unless it were some kind of special model. 32 H&R's are so rare now, you might even be able to sell it as a novelty. I would think you would at least be able to sell it for what a new SP101 in 327 costs, plus you get to keep factory support.

[Castloader]

Try to find a .327 cylinder if they're the same length. I know Ruger is not a great company for spare parts, but you might find something. I'm with Mk42gunner that you'll never be able to sell it after a conversion. If you're confident that it'll be done right and you really want to pay for it, you can give it a spin and see how it goes. The worst that happens is you ruin your gun and have to go buy a .327. They're not hard to find.

[contender1]

One thing to consider. Once reamed,, and you increase the length of the ammo,, your bullet choices may be more limited. Heavier & longer bullets may not "fit" the chambers once loaded in .327 brass.
My humble opinion would be to leave it as is,, and enjoy it as is. If a .327 is desired,, look for one of those to compliment the current one.

[Larry Gibson]

I wouldn't for most all the reasons mentioned. In the SP101 the 32 H&R can be loaded to considerably higher performance that sneak up on the 327 Magnum than the load data in manuals. In 6" revolvers also chambered in 357 magnum you can push the 32 H&R to 35,000 psi and 1500 fps with a 105 gr GC'd cast bullet.

[GBertolet]

I have a S&W 16-4 revolver, and I considered having the cylinder reamed from 32 H&R to the 327 Federal. I know of it being done with no issues, on the 16-4's. But I deceided against it. As Larry stated, the 32 H&R can be uploaded considerably, in higher quality revolvers, such as the SP101, and 16-4. Here is a link on some load data for the 32 H&R. Start low and work up. https://www.handloadermagazine.com/32-h-r-magnum-pet-loads

[405grain]

GBertolet: Thanks for the link to the Handloader article. A real trove of reloading data. ;-)

[nhithaca]

I too vote for leaving the SP101 alone. I own one of these and you can really upload to levels that approach the 327 with bullets in the 100 grain range. The reason that the 32 H&R is as anemic as it is (in factory loads) was that the original H&R guns were limited in strength and most importantly cylinder length. Also agree with GBertolet; make a hard copy of the Handloader article by Brian Pearce and tryout some of these high end loads. You will be more than happy. I have shot loads way hotter than what Pearce has listed in a full sized Buckeye Blackhawk with no issues what so ever. Quite impressive for such a small case.

[nhithaca]

Just for further information, attached is a post I did over at another site showing dimensions of all the 32 caliber revolvers I currently own.
https://singleactions.proboards.com/thread/32677/32-revolvers-compared

[nhithaca]

Here's another post that preceded the first, again about reaming cylinders to 327.
https://singleactions.proboards.com/thread/32455/dan-wesson-32-mag-327

[Outpost75]

Accuracy is impaired jumping bullets from shorter rounds in the longer .327 chamber. The .32 H&R Mag chamber is the best compromise firing either .32 S&W Long or HRM ammo. Larry has pressure test data I fired at Ruger optimized for SP101 which approximates . 30 Luger and .30 Mauser performance from 3" barrel.

[MT Gianni]

I am of the opinion that the 327 F does it's beat with longer bbl lengths. I am not sure what the American Eagle powder is but it is rumored to be MP 300. I think leaving the 101 to it's intended use is well filled with the 32 H&R.

[megasupermagnum]

I am of the opinion that the 327 F does it's beat with longer bbl lengths. I am not sure what the American Eagle powder is but it is rumored to be MP 300. I think leaving the 101 to it's intended use is well filled with the 32 H&R.

While you do gain quite a bit of velocity from barrel length, there are still significant differences with shorter barrels. You can look up some of my work with a 3" SP101. A 327 Federal American Eagle 100gr is up around 1400 fps. I'm not aware of a 32 H&R that is north of 900 fps, unless you are talking hotrods like Outpost75 has made. If you load your own ammo, the difference is not worth anything. If you don't, the 327 offers a really significant gain, no matter the barrel length.

[Green Frog]

I currently can shoot two 327s, a Ruger Blackhawk eight shooter and a custom stainless K frame. I planned to ream a 32 H&R cylinder on a Buckeye Special 32 combo gun from 32 H&R to 327, but collectibility has become an issue. Keep in mind that I’m a guy who had a custom 327 built and was thinking of reboring every gun in sight to the caliber, but then reality sunk in and I realized that none of the manufacturers have made that many guns in 32 caliber that altering them made sense financially, so any 32 H&R that crosses my path will probably remain a 32 H&R. I will entertain thoughts of having an auxiliary 327 FM cylinder fitted to the Buckeye Special though. After all, it already is a combo gun, so it’s made to switch cylinders! Those pesky collectors of the future won’t be cursing my name when I’m gone and can’t defend myself.

Froggie

[MT Gianni]

I have several manuals that show a 98 gr bullet and the 32 H&R at 1100 fps +. My main one is single six mag and it is easily doable with the cases showing minimal base swell.

[Green Frog]

The main shortcoming of the 32 H&R magnum-wannabe wasn’t the cartridge, it was those two letters after the number, “H” and “R”. They didn’t really make a revolver that was up to the job of handling the potential of an otherwise promising cartridge, so factory loadings, though billed as “Magnum” in a word, weren’t! Writers of the time reloaded some rounds for Smiths and Rugers that did live up to the potential, in fact, the late Skeeter Skelton got a little over enthusiastic with his loadings for the little Single Six, and his suggestions made it into print before being pressure tested. I think there were a couple of coronaries and an ulcer or two at the publisher after that!

Fast forward a couple of decades and Federal, who had produced the puny H&R round decided to try again, and with gusto. The old H&R revolvers were no more, and mostly the new round was intended for various Ruger products, although Taurus, Charter Arms and a couple of others produced offerings… even the bean counters in Springfield grudgingly let S&W make a few revolvers for it… but really didn’t tell many folks so they could discontinue them quickly due to “lack of demand”.

Some folks said the Ruger Blackhawk and Smith K frame were too much gun for the “puny” 32 caliber. I humbly rise to disagree. If you want to hold onto a 40,000 psi round with something smaller, feel free to do so. I like to have plenty to hang onto when I unloose a full charge round, and when I’m backing off to something more genteel well, they will certainly handle those rounds too, and the extra weight sure does make them steady!

So there you have it. That’s why my 327s come big! You can do what you want, but that’s how I do it. :bigsmyl2:

Froggie

PS I got so caught up in my own 327 experiences, I forgot all about the initial topic of the thread. IMHO, the SP101 should have enough beef to do the job in question since Ruger did chamber some that way from the factory, right? If I wanted a Ruger DA in 327 Fed Mag though, I’d look for the larger GP100 for the reasons discussed in the third paragraph above. YMMV

[Outpost75]

When I was at Ruger I pressure tested .32 HRM suitable for the SP101 which were in the 30kpsi range. Larry Gibson has that data which we shared years ago before I left the company.

He could repost here without violating my nondisclosure agreement. I cannot.

[Lance Boyle]

When I was at Ruger I pressure tested .32 HRM suitable for the SP101 which were in the 30kpsi range. Larry Gibson has that data which we shared years ago before I left the company.

He could repost here without violating my nondisclosure agreement. I cannot.



Heck I would jump on a 4” k frame along the lines of the model 16. I’d even embrace a seven round cylinder if it fits well and moves the stop notch in between the chambers, and I really prefer my revolvers to be six shooters! I own at least a half a dozen six shooters, no 5,7,8, or 10 shooters.


The pocket revolvers that smith offers in the chambering do nothing for me.

[Ajohns]

I wouldn't, but I'm a fan of the H&R also
My Single Six in H&R does all that any 32 should be able to do for you. Loaded mild, loaded hot, all works pretty darn good.

[farmbif]

altered guns that lost value or can't be sold because lack of interest? I for one would be very interested if could find a marlin 1894 chambered in 32 H&R even it it was reamed out to 327 fed mag

[Green Frog]

I wouldn't, but I'm a fan of the H&R also
My Single Six in H&R does all that any 32 should be able to do for you. Loaded mild, loaded hot, all works pretty darn good.

Who decided what "any 32 should be able to do for you"? My attitude is, if bigger is better and I need (or even want) better, and it can safely be achieved with a truly magnum of the 32 persuasion, well... just bring it on! The 327 FM was marketed as suitable for a self defense round, and if it is looked at objectively, it will be suitable for small to larger medium sized game as well. I would not feel "undergunned" with four inch S&W K frame stainless 327 or Ruger GP100 in 327 for just about anything I would face in my native Virginia (that didn't require a shotgun or a squad assisted automatic weapon!) Your mileage may vary. ;)

Froggie