10mm Magnum Revolver

[Ledslnger]

Originally Posted by agtman

Dude, get yourself focused. Try actually reading the posts and the links to the load & chronograph data that were included.

They're not talking about the 10mm AUTO; they're talking about the 10mm Magnum. Different beast.

I guess I did remember reading that, but got a bit sidetracked and forgot. Lol, sucks getting old.

[porklard]

Yesterday I shot the 180gr HAP on 18.5gr AA#9 with Mag Primer COL 1.555".
They move right along at 1500fps average...
Statistics/Velocity Report

String #: 1
High Velocity: 1529
Low Velocity: 1476

Average Velocity: 1500
Extreme Spread: 53
Standard Deviation: 20
Grains: 180


Velocity # Velocity Power Factor Foot/Lbs
1 1479 266.220 874.199
2 1476 265.680 870.656
3 1496 269.280 894.411

4 1513 272.340 914.854
5 1529 275.220 934.306
6 1510 271.800 911.230

They shot offhand to 3.5 inches at 51feet - better than I usually do with these old eyes.

I compared the primer flattening to the 20gr H110 and they are slightly more flattened but I have seen worse from my 41 Mag with slower velocity.

Frankly, I think I might be pretty impressed with the results - have to muse on that awhile...

[agtman]

I guess I did remember reading that, but got a bit sidetracked and forgot. Lol, sucks getting old.

No worries.

[agtman]

Yesterday I shot the 180gr HAP on 18.5gr AA#9 with Mag Primer COL 1.555".
They move right along at 1500fps average...
Statistics/Velocity Report

String #: 1
High Velocity: 1529
Low Velocity: 1476

Average Velocity: 1500
Extreme Spread: 53
Standard Deviation: 20
Grains: 180


Velocity # Velocity Power Factor Foot/Lbs
1 1479 266.220 874.199
2 1476 265.680 870.656
3 1496 269.280 894.411

4 1513 272.340 914.854
5 1529 275.220 934.306
6 1510 271.800 911.230

They shot offhand to 3.5 inches at 51feet - better than I usually do with these old eyes.

I compared the primer flattening to the 20gr H110 and they are slightly more flattened but I have seen worse from my 41 Mag with slower velocity.

Frankly, I think I might be pretty impressed with the results - have to muse on that awhile.

Those results are impressive! Awesome!

Keep at it, and try some of the heavy hardcasts that are out there.

[disseminator]

'Vastly'?

They make 10mm/.40-cal hardcast 'boolits' that are certainly "suitable for hunting" in weights of 200gns, 220gns, and 230gns, and likely others I haven't seen or tried.

Those - and Hornady's XTP-HP and FMJ-FP bullets - will hold up magnum velocities, such as what S&W 610 owners were getting out of their 6.5" tubes by long-loading the 10mm AUTO past its nominal COAL of 1.250", which is the specified maximum for use in an autoloader.

In a revolver, 610 users (like me) were long-loading the 10mm cartridge out to almost 1.400" and getting near 10mm magnum from the 6.5" guns. You can google and find some of these posts on the various gun-boards, like the S&W forum. A few showed up in threads on THR. I was going to have my own 610 converted to 10mm Mag, but it was an early, first generation 610 and I eventually sold it to a local S&W collector for a hefty amount of cash.

Regardless, the 10mm Mag cartridge makes the practice of long-loading the 10mm AUTO unnecessary, since any halfway competent 'smith can ream-out the chambers of the cylinder to Magnum specs.

The real question is barrel length - longer being better for maximizing the ballistic advantages of the 10mm Mag's output, which is what Ruger's 6.5" 10mm SRH can provide - once 'Magnum-tized' - as a pure hunting handgun. Plus it's easily scoped, whereas the old 610s were not.

On the other hand, for a general purpose 'field'/'woods'/'trail' gun, the 4.2" GP-100 (once converted to 10mm Mag) wins for portability. In fact I'll wager it would be easier to carry around than my 4" N-Frame .41 Mag Model 58, and yet would yield equal or better ballistics than the 58.

Yes "vastly" in that virtually all of the major manufacturers of bullets offer one or more jacketed expanding and soft point bullets in the .410 bore and all the hard cast options are also available to the 41 magnum user up to over 265 grains at least.

The biggest problem with trying to magnumize a cartridge made for semi-auto firearms is that the bullets lack the groove for a proper crimp. I have experienced bullets jumping crimp twice in my own revolvers: once in my 460 XVR with a 400g hard cast and once in my 625JM with a hot loaded 200 grain jacketed hollow point.

Loading a 10mm "long" is only going to make the situation worse due to less of the bullet being in the brass and the lack of a crimp groove for a hard profile crimp.

It can be fun to play around with these types of load and I do it myself in my 625 but I would not rely on those loads for serious use.

I too own a Model 58 and carried it for many years in the woods with 210g soft points and IMO it's a much better choice for that use case.

My own craziest load in my 625 would make you smile: 200 SIG V-Crown HP at 1300 FPS with a big load of vvN105 powder. It makes my 10mm blush.

[disseminator]

As a point of interest: I have occasionally heard of folks running .410 bullets through a 10mm resizer die and then using them in the 10mm. One can only guess the effect on terminal performance however...

[agtman]

The biggest problem with trying to magnumize a cartridge made for semi-auto firearms is that the bullets lack the groove for a proper crimp.

Huh?

What bullets - or boolits - are you talking about?

Right now I load, for example, SNS Casting's 10mm/.40cal 220gn poly-coated hardcast, and those certainly do have a crimp groove. And I crank on the crimp with my Lee Factory Crimp die. Useful load tool, that one.

http://www.snscasting.com/40-s-w-220...-coated-500ct/

I'm also checking out 230gn 10mm/.40cal hardcast selections in anticipation of getting a 10mm GP-100 to convert to 10mm Magnum.

As awesome as it is, I may have to retire my old Mod. 58 to Safe Queen status.

New kids on the block tend to get jealous easily and transmorph into time-vampires. There is, after all, only so much time you can spend at the reloading bench making ballistic magic.

[porklard]

agtman, disseminator still thinks we're talking about 10mm Auto loads in a revolver loaded "long" like Garretj did with his in a previous post

[disseminator]

agtman, disseminator still thinks we're talking about 10mm Auto loads in a revolver loaded "long" like Garretj did with his in a previous post.

No, I don't. I realize you are talking about the 10mm Magnum. But the point I am trying to make is that there is a very short list of suitable bullets for a 10mm Magnum. That is all.

The bullets agtman linked DO NOT have a crimp groove and would require one to roll crimp over the ogive, or into the side as mentioned earlier.

I'm not saying don't do it or anything negative at all, just pointing out there is a shortage of suitable hunting grade bullets.

Fire at will.

[porklard]

I found in a simple Google search for 10mm bullets literally dozens of bullets many of which have a crimp groove. I think it's actually a wonderful thing that I can do the research that I have and that I can now select a bullet that works for ME.

There are bullets for about every conceivable need. A search for .410 bullets finds significantly fewer bullets, many of which do not have a crimp groove, though the percentage WITH a crimp groove is, as you should expect for a revolver round, higher as opposed to the historically semi-auto application for 10mm.

I have been shooting Hornady XTP bullets in 44Mag and 41 Mag for quite a while and have not had any problem with bullet jump, though admittedly I have not taken out the bullets as I shoot to measure for that. I will though and I'll post it here.

[agtman]

Thanks for doing that research. Keep up the good work!

As you continue loading and testing different bullets with the 10mm Mag - whether traditional or hardcast - please post the results you obtain here, including accuracy results. Taffin's presentation of the load data he developed provides a nice guide and model to use.

No doubt his velocity data benefited from the AutoMag's odd-ball length barrel:

The IAI AUTOMAG IV 10MM Magnum with eight and three-eighths inch barrel (measured from the rim of the case to the muzzle end) weighs a hefty fifty-four ounces.

[porklard]

Probably an unscientific and illiterate test but I shot 5 of six loads in a moon clip then measured the remaining cartridge COL at 1.553. Measuring five others from the same lot I got 4 at 1.551, and 1 at 1.552 so maybe I have two thousandths jump which I think I would be happier to call creep.

These were XTP bullets - I loaded 50 yesterday because I'm pretty happy with what I've got so far.

I am going to take agtman's suggestion and get some hardcast lead and make sure I buy the ones with the crimp groove. Of course that crimp will change my pressures so I'll have to back off and load up again.

[GeauxTide]

Ok, my 41Mag Ruger throws 210 Remington SP at 1400, and I've gotten 1500 from 170s. My 4" Smith goes 1300 and 1400, too. Bottom line, the 41 is superior at the top loads.

[agtman]

* * * I am going to take agtman's suggestion and get some hardcast lead and make sure I buy the ones with the crimp groove. Of course that crimp will change my pressures so I'll have to back off and load up again.

A good firm crimp, consistently applied, should help with accuracy too.

[agtman]

Ok, my 41Mag Ruger throws 210 Remington SP at 1400, and I've gotten 1500 from 170s. My 4" Smith goes 1300 and 1400, too. Bottom line, the 41 is superior at the top loads

*Superior* to what?

And what barrel length is your Ruger?

Taffin was getting 1500fps+ and 1600fps+ with 180gn XTPs.

Some of his comments:

Switching to Hornady's XTP bullets, both 180 and 200 grain weights, gave completely different results. Both bullets have solid copper bases and hollow points and are naturals for the 10MM Magnum. All test-firing was done with five shot groups at 25 yards with velocities measured on an Oehler Model 35P. * * * Favorite loads using the 180 XTP are 18.0 grains of AA #9 for 1505 feet per second and a group of four shots at one and three-eighths inches; 17.0 grains of #2400 for 1464 and one and three-eighths inches also; 21.0 grains of WW296 and 22.0 grains of H110 both shot into one and one-half inches with the former going 1625 feet per second and the latter 1662 feet per second.

Switching to the 200 XTP bullet, my particular favorite with the 10MAG, gave even better results than with the 180 XTP. One inch groups are the result of 16.0 grains of AA #9 at 1379 feet per second and 20.0 grains of H110 at 1507 feet per second. The old favorite sixgun powder, Hercules #2400, is not supposed to be a great performer in semi-automatics, but it borders on the fantastic in the 10 MM Magnum with 18.0 grains over Federal #155 primers driving the 200 grain Hornady XTP bullet to 1569 feet per second and making tight little one hole groups at 25 yards.

These are experimental loads only until we know more about the 10MM MAGNUM!!!

[porklard]

I originally posted this (as the OP) in a revolver forum, and Mike Irwin thoughtfully moved it to the reloading forum. Thank you Mike.

Casual comments to the effect of comparison with other calibers are, of course, just fine.

But it is about the 10mm Magnum, it's loading, shooting characteristics, and ballistics.

So when adjectives like 'superior' and other statements like 'fire away' get interjected with the main idea of loading for the 10mm Magnum I just see the far left creeping in to supposed normal peoples conversation.

So if you're only interested in fake news or your opinions, I would personally appreciate your complete silence.

Thank you.

[Ruger45LC]

I just picked up a Ruger Blackhawk .40/10mm with the 6.5" bbl. I'm wondering about future projects with this gun, I've long loaded .40 before but never have had the chance to long load 10mm.

I'm wondering how hard it would be to see if Ruger would sell me (and fit) an extra (third) cylinder? I'd probably have to send it elsewhere to get reamed out but I don't want to lose the ability to shoot .40. I wouldn't mind 10mm Mag just because starline makes brass for it, that's a huge plus, and because it's in a revolver, you could long load the 10mm Mag too.

Then again, something like the 401 Powermag would be cool as well and give even more power, but brass is very pricey and I'm not sure I'd want to fashion it out of .41 Mag brass all the time. But with either one, for heavier hunting stuff you could swag down some .41 cast boolits, you'll just have more room for powder in the Powermag.

[phenson425]

This is my first post to this forum and
I joined because of this thread. I own two 10mm Magnum revolvers, a S&W Model 610
6 1/2” barrel and a Ruger GP100 3” barrel. I have done a bit of research on load data, but I’d still like to get some more information. If I can be a help to anyone, please let me know.
Pat Henson