Loaded up .40S&W cases at 10mm length

[jazzsax8]

Read about doing this for years and finally did it after looking over my primer stash where I have twice as many small pistol vs large.  Did a lite load of 5.7gr Green Dot with Lee 175 lead at the normal COAL of 1.255.  Now I have read that the Glock's will digest thousands of these with no ill affect but what about my new Ruger SR1911?  After drop testing some in its barrel it was obvious that the COAL did not affect the rounds ability to go way deeper into chamber than the longer 10mm case.  With our cases averaging .985 or even less that would seem to be enough short of the chamber dimension that ALL rounds in ALL pistols are being held by the extractor.

I will try them in the G20 w/KKM barrel and of course check the chamber and scrub it before introducing any full length 10mm cases.

Whatsayou?

[Graybeard]

There may be other here that will argue they've done it, but I wouldn't shoot 40s out of a 10mm barrel in a 1911 with an internal extractor. Since rimless autos headspace on the case mouth, the 40s will not hit the end of the chamber. They will dangle on the extractor. It adds stress to the extractor that the gun wasn't designed for. You could get light hits, the extractor going out of tune, and chipping of the extractor hook.

External extractors work differently as they pivot on a pin with the force of a spring on the back end. Internal extractors in 1911s are themselves a flat spring with a hook on the end.

There are plenty of barrel makers that will make you a barrel that will accommodate the load you're making. It's just a matter of a longer throat in a 40 barrel and the rifling starts a little farther out.

[jazzsax8]

Graybeard

I like your take on this difference in the extractor and agree that a custom barrel is beyond ideal.  I have complete confidence that the Glock 20 will handle it with no problem.  What intrigues me is that my cases might average .985 going as short as .979 but the chamber dimension is supposed to be .992.  If the case head in my 1911 Ruger is being held in place with a little tension as it is. how would the alleged headspaces on the cartridge rim ever occur.  In my way of thinking if its up to .013 of space would it matter if it was that or even 5".  In my reasoning all short 10mm brass which it seems to be, never headspaces correctly in all formats?

[The_Shadow]

Many 10mm firearms can shoot the 40S&W cartridge from the 10mm chambered barrel.  The issue comes from the shorter cartridge being held in position by the extractor alone when being fired.
The use of the 40S&W ammo or long loaded 40S&W cases can pose an issue where the bullet passing across the end of chamber cut can shave off bullet material where it can deposit against the sharp cut that defines the end of the chamber.  You might shoot many rounds without incident, but then again the buildup from deposits there can cause failure to completely feed, out of battery condition the the most sever being the deposits causing a restriction that can raise the chamber pressures.

Also the shorter casing leaves a little over 1/8" of exposed chamber where the carbon can build up and that deposit would need to be thoroughly cleaned for reliable use of the 10mm ammo.

I will say that having the 40S&W conversion barrels for several of my 10mm guns makes it an easy transition to utilize the 40S&W cartridge safely.

[Graybeard]

All guns are designed with tolerances in mind. No manufacturer of ammo is going to make millions of cartridges with brass the same length down to the thousandth.

Next time you have your gun apart, drop an empty in the chamber and look where it stops relative to the notch the extractor engages. It is my suspicion, because I have no way to measure it, nor x-ray vision, that the extractor can pass slightly beyond the rim of a case at the longer end of the range of tolerances. Therefore it can  also handle slightly shorter cases and still allow them to headspace.

I suspect there are some guns that do exactly what you propose, as I've seen 1911s that seem to beat their extractors up and go out of tune. The vast majority don't.

I would be very curious if anyone knows of the brass length tolerances a current manufacturer of 1911s in 10mm uses in making their guns.

[The Earl o Sammich]

Read about doing this for years and finally did it after looking over my primer stash where I have twice as many small pistol vs large.  Did a lite load of 5.7gr Green Dot with Lee 175 lead at the normal COAL of 1.255.  Now I have read that the Glock's will digest thousands of these with no ill affect but what about my new Ruger SR1911?  After drop testing some in its barrel it was obvious that the COAL did not affect the rounds ability to go way deeper into chamber than the longer 10mm case.  With our cases averaging .985 or even less that would seem to be enough short of the chamber dimension that ALL rounds in ALL pistols are being held by the extractor.

I will try them in the G20 w/KKM barrel and of course check the chamber and scrub it before introducing any full length 10mm cases.

Whatsayou?

I wouldn't do it, based on some of the replies above.  Do you need some 10mm cases?    ....and I got a shit ton of Large Pistol Primers.    ....looking to trade for some Small Rifle Primers.

[jazzsax8]

Shadow

Knew about the dangers of carbon build up but had not considered lead shavings!  Good thing I only have 100 of the 175 Lee Lead to shoot up.  Shot 18 of them yesterday with 5.7gr Green Dot and they did 1020fps s.d. 34 where 9 rounds at 25yds went into 3 7/8" & 5".

Same load 18 rounds with 180gr JFN did 900fps s.d. 28 where 8 of 9 into 3" and 7 of 9 into 2 1/2".  Some of the primers looked quite a bit flatter than average but the crony did not show anything much faster.

Just looked at some .40 S&W barrel options and will need a little help doing the right thing.  Ramps, nowlin, clark/para and etc.  The Ruger has the ramped bull barrel .699 and would love to get something not needing too much gunsmithing.  Cheaper end looks like Rock Island for $80 that might fit.  Yes many in the $200 range but not sure I need that unless they are way more accurate.  Any recommendations here would be appreciated.

Cleaned the barrel and did not find any shavings or build up but did not expect so in 36 rounds total.  I will use the Glock 20 to use up the 200 rounds I have loaded up until I get a barrel for the Ruger.

Earl o Sammich
Thanks for the helpful offer but I have more 10mm brass than I could ever wear out and do have 3K primers LP but 6K small.  I do not have enough small rifle to consider a trade.

[Graybeard]

https://www.szbarrels.com/Portals/0/Documentation/Webfile_Identify%20Your%20Barrel%20Ramp.pdf
The link should help identify which barrel you would need. OD really doesn't matter as you want a matching barrel bushing for best accuracy.

[gnappi]

I think getting a .40 barrel (and mags with the spacer in the rear) is:

1. Barrels are available where primers are not.
2. Cheaper than say 500 primers at today's prices
3. Safer and more reliable

My mom used to say... "Just because a thing CAN be done does not mean a thing SHOULD be done"

I often think about that when I consider doing something foolish :-)

Add to that you're likely to have bullets coming loose set out so far.

[bigboredad]

If you are looking for a barrel for your Ruger sr1911 10mm I believe it is the Wilson/Nolin style and also remember it is a bull barrel.  I've looked at doing the same thing a year ago then the political b.s. and could put everything on hold. I have run factory 40s and reloaded 40s both loaded to 1.125 and have had no I'll affects that can be seen.

Sent from my SM-T377V using Tapatalk

[jazzsax8]

A big thank you Graybeard for the link to ID the ramp.  It is the Wilson/Nowlin style also mentioned by bigboredad.  I assume that the other style Clark/Para is not supposed to fit.  Now the question, some of the Rock Island barrels having the ramp on eBay do not specify which ramp is there.  Yes, I can ask but that might imply both fit!

Graybeard, due to you while inspecting my barrel, I discovered a crack in the lower barrel lug from the rear bottom corner going all the way over to the link pin hole!  You can see daylight through the first 1/16" and the crack is on both sides.  I guess it would not have hit me on the head if it completely turned loose but might have messed up other pistol parts if it did.  Contacting Ruger Monday for the return.  I just hope they will not replace the polished trigger components that has my trigger at only 3.5#'s with no creep.

Another SPP solution I am looking for is to find some SPP brass vs. a barrel.  I am a little concerned about getting a barrel fitted correctly knowing just enough to be dangerous.

With the 29# mainspring I am surprised that it cycled all 36 rounds the other day perfect including hold open on the last shot.  A few rounds did not make it off the shooting bench. 

[Graybeard]

Wow, I'm glad that you found that crack before it completely failed. It's unlikely that it would have caused you any physical damage, but it may have become a disassembly nightmare.

The two different ramp designs will not fit in the same gun. IIRC, one is wider than the other where it fits in the frame and that's just the beginning. Sorry, I've never owned or seen disassembled an RIA .40 and have no idea which design they use.

I've never sent a gun back to Ruger with any aftermarket parts as I've heard that they will replace them with originals. If you just polished up the original parts, they'll probably leave them alone. Your issue only has to do with the barrel.

Good luck with it. Hopefully they'll turn it around quickly for you.

[jazzsax8]

Graybeard

I will remember you for a long time as I check that area especially after firing the nuclear loads.  I might not have ever found it just cleaning the barrel and did not the other day just cleaning the barrel!

I sent two Ruger Mark II uppers to them last year to get drilled and tapped and the service was quick around 10 days door to door.  If they have it this time for over a month, I will survive with plenty of stuff to play with.  I think I will put a note with it saying if you replace ANY parts other than the barrel, I need the originals returned to me in a bag!!!!!  I did barely touch the sear surfaces with crocus cloth so they are probably more shiny than stock.  I am just afraid if they test the trigger at 3.5#'s it will cause them to take a look at it.  I think these average closer to 5.

[sparkyv]

Same goes for me, no issues shooting 40S&W in my SR1911-10, but I don't shoot many of them, and I did pick up a spare extractor, just in case. 

I have run factory 40s and reloaded 40s both loaded to 1.125 and have had no I'll affects that can be seen.

Interesting, mine did the same last year.  [Edit: added link to original post]

http://10mm-firearms.com/10mm-semi-auto-handguns/sr1911-10-barrel-lower-lug-is-cracked/msg87947/#msg87947

I've seen about half a dozen or more posts about this over the past couple of years, so it seems that it's not too uncommon.  Ruger replaced the bbl with no comments on the cause, but they did send me the obligatory silicone wiping cloth as a consolation. They left my polished stock trigger and parts alone.  Works like a champ!

Graybeard, due to you while inspecting my barrel, I discovered a crack in the lower barrel lug from the rear bottom corner going all the way over to the link pin hole!  You can see daylight through the first 1/16" and the crack is on both sides.  I guess it would not have hit me on the head if it completely turned loose but might have messed up other pistol parts if it did.  Contacting Ruger Monday for the return.  I just hope they will not replace the polished trigger components that has my trigger at only 3.5#'s with no creep.

[Graybeard]

Graybeard

I will remember you for a long time as I check that area especially after firing the nuclear loads.  I might not have ever found it just cleaning the barrel and did not the other day just cleaning the barrel!

I sent two Ruger Mark II uppers to them last year to get drilled and tapped and the service was quick around 10 days door to door.  If they have it this time for over a month, I will survive with plenty of stuff to play with.  I think I will put a note with it saying if you replace ANY parts other than the barrel, I need the originals returned to me in a bag!!!!!  I did barely touch the sear surfaces with crocus cloth so they are probably more shiny than stock.  I am just afraid if they test the trigger at 3.5#'s it will cause them to take a look at it.  I think these average closer to 5.

Well thanks I'm just glad you didn't end up with a locked up gun/partially chambered live round/ cut off the slide stop and pound it out scenario.

I'm also glad Sparkyv chimed in. I've always had a problem regaining trust in guns that fail out of the box. It's good to hear that Ruger did right by him and he's had no further issues.