The S&W 610 10mm Mag revisited.

Just picked up a new S&W 610 and the cylinder is in the capable hands of Mark Hartshorne at Pinnacle High Performance to be reamed and chamfered to accept the 10mm Mag.
Picked up a spare cylinder from Midwest Gun works in case there are any issues.
I was surprised to find that 10mm and 10mm Mag was easy to come by in these days of shortages and it was reasonably priced.
Picked up 1740 rounds in .40,10mm and 10mm Mag for $1400 bucks.
If I can get rounds for under a buck a piece these days I'm pretty happy.

So any new info out for those of you who have done the 10 Mag conversion?
I've scoured the internet but there's just not a lot of info out there.
 
I suggest you set up a dedicated press for 10mm and start cranking out practice ammo. $1 a round is easy to beat.:rolleyes:
 
:rolleyes: It's in the works.
Have a Dillon 1050 on order. As far as practice ammo goes it'll shoot the .40 as well as the 10mm.
Ammo is readily available for all three calibers in the meantime.
I have plenty of rounds in 5.56,.45 ACP and all my other rifles and pistols,I've always been a squirrel when it comes to stocking up. I've been recovering from multiple hip surgeries over the last two years so I really havent been able to shoot at all so the ammo shortage has been the least of my worries.
I'm far from a newb when it comes to firearms,been shooting for 47 years at this point.
But thanks for your reply.
 
I also purchased a S&W 610-3 10mm recently and have found factory ammo to be sparse but there has been some.
Luckily I already load .40 S&W so moving to 10mm was just a matter of moving my dies out some and procuring some bullets heavier than 140gr.
The pistol shoots absolutely great also.
There was one supplier that had Starline Brass but I think I got his last 300.
 
I think 10mm is way overrated online.

However, the thought of it in a revolver kinda seems appealing. 38/357 isn't always cheap even during normal times. My interests in revolvers is purely for fun at the range...this is kinda of a winner idea.

Wish the 610 were a L frame with 7 rounds though...
 
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10mm Mag is something I wish more gun writers would investigate, from what little I've read it's equal in power to .41 Mag and between .41 Mag and 10mm Mag, I'd rather have 10mm Mag, but I would greatly prefer it be a rimmed cartridge because I know of no autoloaders made in the chambering for decades and I prefer a rim because it allows roll crimps to be used.

I actually wouldn't mind having both a rimmed and rimless 10mm Magnum that why I have the choice between using moon clips or not. We already have that with .45 ACP and .45 Auto Rim, so there is a definite interest in a revolver that can do both and it gets me to thinking that had Charter not gone belly up in the early 90s the 9mm Federal may have proven itself popular over time.
 
Hey 610 pros, is the 610 on the "N" frame similar in size to the 627 357 8 shot cylinder? I can't google this right to figure it out.

The 627 8 shot 357 cylinder just looks huge in person. Does the 610 have the same ugly appearance being they are both N frames?
 
I think 10mm is way overrated online.

However, the thought of it in a revolver kinda seems appealing. 38/357 isn't always cheap even during normal times. My interests in revolvers is purely for fun at the range...this is kinda of a winner idea.

Wish the 610 were a L frame with 7 rounds though...
While you're entitled to your opinion, it's obvious that you're not shooting full power 10mm loads (if you've ever even actually shot a 10mm) as the 10mm can be loaded as a more powerful round than one thinks.

I shoot both .357mag and 10mm and in a 6" barreled pistol, the 10mm using full power handloads (not the under powered factory stuff) is superior to the .357mag. Yep, I said superior. A larger, heavier bullet traveling faster and producing much higher muzzle energy. I'm guessing that the 10mm mag is even better.

Chrono'd data shows that my larger .40 cal, heavier 165grn, hot 10mm handloads shot from my custom 6" G20L I developed way back in 2004 produce velocities of as high as 1,589fps with a ME of 925ft/lbs at my range at 6,100ft asl on an 84°, sunny day.

Compare that to my .357 cal, lighter 158grn, hot .357mag handloads shot from a friend's 6" S&W 686 (my .357mag pistol is a 7½" Uberti SA and not strong enough for full power) producing velocities of 1,491fps with a ME of 780ft/lbs at my range at 6,100ft asl on the same 84°, sunny day.

HOWEVER, if one is talking about performance from a longer barreled firearm, say a levergun, the .357mag's larger case and slower burning magnum powder gives it a huge advantage over the small cased, fast burning powder powered 10mm.

Again, chrono data shows that the larger cased .357mag loads above fired out of my levergun can produce velocities up to 500fps faster than from my friend's 6" barreled 686. Velocities with the load above as high as an astounding 2,005fps with a ME of 1,410ft/lbs out of my 24" rifle!!

Now compare that to the rather modest gains the 10mm produced of just over 200fps increase out of a friend's 10mm carbine over the best I can produce from my G20L and it's clear that the .357mag handloads produce spectacular results in leverguns.

That's not opinion, that's actual data I measured from over 16 years of shooting full power 10mm in my G20L and over 11 years of shooting .357mag in my leverguns and I stand behind my data.

Wild cat, where's your data?
 
I would think a rimmed 10mm Magnum would be easy to make from 30-30 brass. Then again, wouldn't that be a .401 Herter's PowerMag?
 
So you are hand loading hot loads. Okay. Got it. That's pretty atypical.

But you aren't shooting a hollow point that benefits from increased FPS. So what are you shooting where this matters?

That's why I say it's overrated. Even the 357 has this problem. A FMJ 380-45 is going to go 32" in gel. A copper wrapped FMJ isn't really deforming on impact on a target. With a Hornady thick copper FMJ (lead core) jacket...even a .40 could outperform typical "outdoor" hardcast in 357 or 10mm. Take the Lehigh solid copper non expanding? Even the Penetrator 380 defeats ballistic glass.

Heck, your random box of any 9mm FMJ might do just as well on target results. No one is debating the FPS is higher. But to what point? FPS in a handgun doesn't do what a rifle does. So what does even 400fps more from a FMJ accomplish on target? Modern HST/Gold Dot doesn't need or benefit from massive FPS. Even XTP which is not bonded at the pedals doesn't benefit from high FPS.

THAT SAID...

I'm being pro 10mm for a minute. Help me out on that cylinder question. Same size as the HUGE 627? I didn't think the 627 looked big until I saw it in person. Almost laughably big. Haven't seen a 610 in person. Same look?
 
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So others know, wild cat believes that 9mm is the quintessence of all handgun calibers to the extent that no other caliber need exist.

The fact remains that a heavier bullet that doesn't expand and has a higher velocity is going to penetrate straighter and deeper. For self defense against people, an FMJ or solid bullet is a poor choice, for predatory animals a solid bullet is a good choice given you're likely going to be shooting it as it charges you and ideally you'd like the bullet to exit so as to produce as much damage as possible.
 
9mm NATO or Major has higher velocity than most commercial 357 or 10mm at 1200-1300fps.

Lucky up Lucky Gunner. The 357mag XBP at 1,600FPS went 20" in their gel and expanded to .63 inches. Well...so did the 9mm 147gr HST at 1,000FPS.

HST poster from Federal:
https://www.kiesler.com/SiteContent/catalogs/HSTInsertPoster.pdf
Vista Outdoors' Gold Dot/HST comparison website:
https://le.vistaoutdoor.com/wound_ballistics/load_comparison/load_comparison.aspx

Anyone on that cyliner size? Jonesing for the 610 in 4" and have one in my cart to buy. Still haven't found cylinder size info.
 
If it's any help on cylinder size my 610 cylinder width is right at 1.710 and the cylinder from my Blackhawk .41 mag is at 1.730-maybe this is a help.
 
Please don’t take this question to be argumentative, but I’m curious. Why? I can’t see this doing anything my .41 mag does. As a hand loader I’ve down loaded as low as 4gr of Green Dot for very mild shooting, all the way up to fairly stout XTP’s. And the guns for this already exist in both revolvers and lever action rifles. Now I get it if it’s just for the fun of doing something different, if I could afford it I’d have all kinds of wildcat stuff for S&G’s. But is there some advantages that I’m missing here?
 
Please don’t take this question to be argumentative, but I’m curious. Why? I can’t see this doing anything my .41 mag does. As a hand loader I’ve down loaded as low as 4gr of Green Dot for very mild shooting, all the way up to fairly stout XTP’s. And the guns for this already exist in both revolvers and lever action rifles. Now I get it if it’s just for the fun of doing something different, if I could afford it I’d have all kinds of wildcat stuff for S&G’s. But is there some advantages that I’m missing here?
If you already have a .41 Mag, then no. The advantage for 10mm Mag is for people who already have semi auto's in .40 and 10mm and would like a revolver the size of a .357 (like the GP100) but have a heavier bullet that can expand from a handgun barrel or have more power.

The 10mm Mag is still largely unknown because few have experimented with it over the years. Starline has made brass for it for a while, but guns weren't available. That changed with the resurgence of 10mm that lead Ruger and S&W to make revolvers in the caliber, revolvers that had cylinders long enough to accommodate the 10mm Magnum if the chambers were reamed deeper. It's only recently that guys like Jeff Quinn (RIP) brought it to people's attention, myself included.

My hope is that the 10mm Magnum will start to come out of the shadows. I truly think it can be everything the .41 Mag was supposed to be.
 
Power wise, not much AND most options are at .40 level weight and velocity. But the 610 takes .40

The .40 comes in factory loaded gold dot and HST. You could shoot 40 premium ammo at the price of kinda junky 357. Premium 357 just isn’t loaded like 9mm/40. That is where I see the advantage of a 10mm revolver. Especially since 38/357 is nonexistent right now.

It takes a hot hot load to beat 357 and 10mm only compares to weak 41mag. It’s hyped, but here in the 610....appealing for sure
 
A 610 chambered in 10mm mag would make one heck of a dandy hunting revolver. I wish you the best with your pursuit.
from the looks of it- 10mm mag is in the ballpark with .41 mag which is well regarded for deer hunting.

Plus, being able to shoot std vel .40 s&W for practice would only add to its versatility.
 
If you already have a .41 Mag, then no. The advantage for 10mm Mag is for people who already have semi auto's in .40 and 10mm and would like a revolver the size of a .357 (like the GP100) but have a heavier bullet that can expand from a handgun barrel or have more power.

The 10mm Mag is still largely unknown because few have experimented with it over the years. Starline has made brass for it for a while, but guns weren't available. That changed with the resurgence of 10mm that lead Ruger and S&W to make revolvers in the caliber, revolvers that had cylinders long enough to accommodate the 10mm Magnum if the chambers were reamed deeper. It's only recently that guys like Jeff Quinn (RIP) brought it to people's attention, myself included.

My hope is that the 10mm Magnum will start to come out of the shadows. I truly think it can be everything the .41 Mag was supposed to be.
This still requires not only the purchase of another revolver, the modification of that revolver, and another another caliber of equipment and components just to do what already exists with the .41 mag. The versatility of being able to shoot three different rounds in one gun I get, but if you already owned a semi auto for 10mm/.40 why would you want a revolver for the same? Plus you lose the possibility of a lever in the same caliber for some rifle performance too. And the use of moon clips is also going to be mandatory to use .40 and 10mm. BUT, if you want to do it and have some fun doing it I’m all for it.
 
This still requires not only the purchase of another revolver, the modification of that revolver, and another another caliber of equipment and components just to do what already exists with the .41 mag. The versatility of being able to shoot three different rounds in one gun I get, but if you already owned a semi auto for 10mm/.40 why would you want a revolver for the same? Plus you lose the possibility of a lever in the same caliber for some rifle performance too. And the use of moon clips is also going to be mandatory to use .40 and 10mm. BUT, if you want to do it and have some fun doing it I’m all for it.
Good points, ones I've thought of and while it's not a dealbreaker, I do like the ability to use 10mm Auto without a moon clip, but being able to run 10mm Mag makes it worth doing. .40 S&W requires a moon clip in any 10mm revolver, be it Auto or Magnum. Most people who own a 10mm revolver already assume that it must use the moon clips to eject the cases, so that's not a big deal to them.

For those who already reload .40/10mm Auto, it requires nothing else in terms of equipment for 10mm Mag.

I don't have any interest in a lever action 10mm Mag and it's not like there are a lot of options for a lever in .41 Mag either other than Henry. There are companies that make 10mm Mag barrels for Thompson Center single shots, but I'd have no interest in them either in 10mm or .41 Mag.

All that said, if someone already owns a .41 Mag gun, then there's little need to get into 10mm Magnum. The 10mm Mag is for people like myself who are big into .40 and 10mm, but wouldn't mind having a revolver the size of a .357 that's basically capable of shooting .41 Mag power levels while also being able to shoot the shorter .40 and 10mm Auto, which they shoot in their semi autos.

The requirement to modify the 10mm revolvers tho is the biggest hurdle, one that would be removed if Ruger and S&W would chamber the revolvers in 10mm Mag, but they won't do that because they know how clueless potential buyers are when they see it's for 10mm Mag, not Auto and they'll think the ammo costs $2 a round and can only be found at the edge of the Earth, so they won't buy it.
 
This is a cool conversion that I've seen a few folks do. I'm not ready to do this to mine just yet, but I'm planning to long-load the 10mm Auto to see how close I can get to the 10mm Mag. Does that spare cylinder need to be hand-fit? You can get some more info at the 10mm-firearms forum.

Just picked up a new S&W 610 and the cylinder is in the capable hands of Mark Hartshorne at Pinnacle High Performance to be reamed and chamfered to accept the 10mm Mag.
Picked up a spare cylinder from Midwest Gun works in case there are any issues.

So any new info out for those of you who have done the 10 Mag conversion?
I've scoured the internet but there's just not a lot of info out there.



Yes, basically the same size, but that 6-round 610 cylinder has alot of meat on it vs. that 8-round 627 cylinder to handle the higher pressure. I like the N-frames, I thing they look great. :cool:
THAT SAID...

I'm being pro 10mm for a minute. Help me out on that cylinder question. Same size as the HUGE 627? I didn't think the 627 looked big until I saw it in person. Almost laughably big. Haven't seen a 610 in person. Same look?
 
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