does anyone cut down 10mm to .40 S&W length?
if so any notable things to consider? (other than 10mm large primer and .40S&W small primer)
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does anyone cut down 10mm to .40 S&W length?
if so any notable things to consider? (other than 10mm large primer and .40S&W small primer)
I can't imagine anybody doing this. 40S&W brass is all over the range. 10mm is not, and is expensive.
PM me. I’ll give you two for one. 2 40 cases for one 10mm.
I don’t even own the 10mm yet.
I agree not worth the time and 10mm is in high demand now so I would just trade and save your time. I can offer you the same deal 2 x 40 for 1 x 10mm as well and you wont have to bother cutting anything down.
Also if you cut down 10mm to .40 S&W, you also need to mouth ream them. Labor intensive.
^^^ What DanishM1Garand said... except I have 3 10mm's and can never have enough brass to feed them.
i'm not looking to trade...doesn't anyone actually read and comprehend each word in a sentence?
the question was purely that...a question.
Im sure someone does. There are a lot of people out there loading. One of them is probably in a situation where 40 s&w brass is hard/impossible to get and 10mm is easy, maybe its illegal to own a 10mm auto firearm and illegal to own 40 s&w brass.
I dont know any of these people so cant attest to any issues they have ran into.
Consideration: the brass may get too thick in the case wall as you trim down the length to 40. This would cause a problem. The case mouth might swell to a diameter too large for the gun’s chamber.
I am a 40S&W fan. Load it hot or light.
Okay the 40 S&W and 10 mm are very close other than length. cutting down 10 mm to 40 S&W was the how the original testing was probably done. Things I would look at are internal case tapers the 10 mm may have a heavier taper in it and need reamed to make bullet seating room with out bulges. 10 mm is large primer and 40 data is for small pistol so loads should be dropped and worked up but not a big deal. Last that should be checked is the case head thickness heights so capacity may be lower or different
I'm pretty sure that we did understand the question and I believe we all answered. Can it be done? Yes. Is it worth the time , effort and frustration, probably not.Quote:
Originally Posted by mozeppa
As many pointed out besides cutting those down you might have to deal with brass being too thick now so thats another step plus when its all said and done you'll end up with 40S&W brass but with large primers because 10mm uses LP and not SP primers so you'll have to develop your loads from nothing as there will be no published data for 40S&W brass with LPP.
As I get older I realize that its easier when you dont try to reinvent the wheel but if its something that you are dying to try and have time to play with then more power to you. I wont stop you. I'm actually curious how that works out.
It's called the "Centimeter".
Those crazy old IPSC guys did it way back when (that's where S&W got the idea for their .40).
Like others have said, necks have to be reamed and the thick brass also reduces case volume, add the LP primer and high working pressure and powder selection becomes critical.
Not really relevant to your question, but another complication at the time was the trend toward heavy-for-caliber bullets to reduce felt recoil. Those guys were launching 200 and 220 grain bullets at 900 and 820 fps to make the old 180PF. There were very few available powders at the time suitable for the task (the situation hasn't improved substantially), and there were no SAMI specs or reloading data available to guide those intrepid pioneers in their quest for the ultimate IPSC cartridge.
Interesting times.
Hope this helps...
Jerry
I'd think yes, similar maybe to making 9mm Makarov from 9mm Luger. Constantly amazed at the judgement introduced in responses. It's a case forming forum, making sense isn't one of the criteria. Bravo to the original poster for asking. Take it a step further, make 40 from 10 then make 45 jacketed bullets from that new case. (Geeez but jacketed bullets are available everywhere!). And as I think about it, why cast? Cracking up here on a cold Indiana morning......
for those who say "ream the case mouths"
....my 180 grain boolits are nearly as different from my 150 grain boolits in length as the .40 S&W is from the 10mm.
so what i'm saying is that the 150 grain boolit would sit no deeper into a cut down 10mm case than a 180 grain boolit does in a "non cut down" 10mm case.
so in reality ....there would be virtually the same volume under the base of the boolit ....so again, why would reaming be necessary?
I think this pretty well covers it.Quote:
Originally Posted by marek313
It sounds like no one does it. It looks like a lot of work to make a case thats readily available. I see 2 potential problems with this. The case walls possibly being too thick and working up a load with large primers.
But it will be interesting to see your results
why??
Must be a good reason...just not apparent.
I'm still sitting on 40 or 50 lbs of 40 cal brass that I don't reload anymore that will get re-purposed into bullet casings.
I RSO'd a local pistol range yesterday. I could have walked away from there with a five gallon bucket of .40 S%W brass, I think it's even more common than 9mm brass now. I really should get a .40 if for no other reason.
I have a 10mm I occasionally shoot, one of the few auto pistols that I really, really like. Wish I could pick up 10mm brass like that.
Frankly I don't see much problem using LPP in one as I've read numerous posts elsewhere of people using SRP in them with good results. Just lower the starting load and have at it.
How many on here have experimented with rifle primers in pistols or magnum primers in place of standard? I know I have.
I am wondering if the reaming comment actually meant chamfer?Quote:
Originally Posted by mozeppa
No, I'm pretty sure they meant ream. Anytime you shorten a case, pistol or rifle, the case walls (thicker) become the neck/case mouth. If the chamber had minimal clearance before, then you run the risk of causing high pressure events when the bullet can't release easily from the case neck. Per his 150/180 reference, I'd suspect that he wouldn't have a problem, but there is a point below the normal seating depth where the brass thickens noticeably with heavier for caliber bullets. When I load 200 grain in the .40 cases, they start to bulge at the bullet base.Quote:
Originally Posted by Plate plinker
I've considered it, as I've had a few 10mm cases here and there with crinkled or cracked necks, that I've tossed into the scrap bucket. I look at them, look over at the gallons of .40 S&W brass that is so cheap and plentiful as to be sold for scrap, and I toss the 10mm brass into the scrap.
I've been known to be stubborn and curious and do silly things like that just for kicks (and to see if it can be done), but nowadays I don't seem to have as much patience and curiosity for it.
I'm with everyone else. If someone GAVE me 1 million rounds of 10mm brass and all I had was a .40 S&W, I'd either sell the brass and buy .40 brass, or else buy a 10mm pistol.
I'm sure somebody does. And I'm equally sure that somebody has also traded an ounce of gold for an ounce of silver at least once throughout history. And somebody has bought a used Yugo on a 72 month loan.Quote:
Originally Posted by mozeppa
It doesn't make economic sense, so therefore I would imagine not very many people do it.
Let me add that once, when I was young and much poorer, I did trim down 50 pieces of .357 Mag brass to .38 Special length. It had begun to experience case mouth splits, and I couldn't afford new brass at the time. I was a young soldier with a wife and baby son; no money for stuff like brass! I would not do that again, for a variety of reasons.
I've started trimming down 10 to 40. It allows me to use a surplus of LPP and take pressure off my SPP stockpile.
Noooooooooo! You may have really angered the 10mm gods by doing this.Quote:
Originally Posted by a075923
Heck, PM me and maybe we could work out a deal and I could send some primed 40 cases to you in trade for the 10mm ones.
Curious if the OP ever tried it or was just blue sky questions and got tired of being whacked for asking a simple "what if question".
I've done weird things in the past just to see if the could be done. 45 Colts on a 444 case to shoot in a T/C 410/45 Colt barrel(it works). Did it just for the grins of it during the house arrest last spring.
Will probably get in the same kind of silliness this winter if we don't get good ice for sailing this winter.
Better than watching Judge Judy.
I saw skrapyard628's post and I'll do the same thing. I've got probably 600-700 pieces you can have. Heck, just pay the postage and you can have them.Quote:
Originally Posted by a075923
Wouldn't hesitate one second using magnum SPP in place of regular SPP, but would hesitate using SRP in place of SPP, especially with striker fired pistols. Hammer fired would prolly be OK, but have seen some striker fired pistols have trouble with regular SPP, and SRP are said to be harder cups, or so they say.Quote:
Originally Posted by jonp
Sorry I've already trimmed the 250 or so I've picked up.