30 carbine primers

[dg31872]

I have looked and not found info on when to use cci 41 primers or cci450 or cci400 with H110 in 30 carbine. When do you use the milspec or the regular? Does the 41 help prevent slamfires? Are the 41s hotter than the 450s? Thanks is advance.

[Larry Gibson]

I've used the 450s and WSRs for many years and many thousands of .30 Carbine loads w/o a problem. Both are for use with ball powders. I suspect if correct loading procedures are followed with the primers seated completely that slam fires are as possible with reloads as with milsurp or commercial ammo. Anyone ever heard of "milspec" primers ever being used in 30 Carbine ammo, commercial or milsurp?

Larry Gibson

[Mk42gunner]

As far as I know, the harder cup CCI primers came out after people started to load AR-15's frequently. Or it could be because they were making a Large Rifle they decided to market Small Rifle primer also.

It has been years since I had an M-1 Carbine bolt apart, but isn't the firing pin a lot smaller (less inertia) than the one in an AR-15/ M-16?

My Hornady Handbook of Cartridge Reloading fifth ed. uses WSR primers in both the 5.56mm and .30 Carbine, and WLR in both the 7.62mm NATO (M-1A) and the .30-06 (M-1).

I have seen a lot of primers marked by the firing pin on both M-16's and M-14's while serving as a Rangemaster in the Navy; after reading of the CCI milspec primers I got curious and paid more attention. I really don't see how the very slight mark (not even enough to be called a dent), on the primer could ever set one off.

I never saw it in a summary of mishaps either.

The harder primer cup may be necessary for some rifles; but it may be one of those "Hey it sounds good and will probably sell a million or two" ideas.

Robert

[cwheel]

In my last loading of 30 carbine, I did get some slam fires. Note that the slam fires, with CCI standard small rifle, happened with loading as a single round only, and never when feeding from a mag. Cases were primed properly, primers properly seated. Rounds that didn't slam fire ( that is most used this way ) did receive a small indent from letting the bolt fly home under spring pressure from lock. This happened with both of the 2 Winchester carbines I have. Bolts were disassembled, inspected, both were clean firing pin channels were clean and unobstructed, firing pins floated freely. My conclusion on this is that the lot of 5000 small rifle primers I bought in that lot were overly sensitive. Next loading of carbine I will get mil-spec primers, understand that they are somewhat harder. Note that the cases that did slam fire showed the same small indent from firing pin contact that the rounds that didn't fire displayed, not as deep as a full hammer to firing pin hit. Still enough to fire the round. First thing I'd advise, always load and fire from a mag in the gun, slows the speed of the bolt enough to not have inertia drive the firing pin into the primer as hard. I wasn't using a mag shooting off a bench doing load development for this short run of ammo. Cases were already primed, will cautiously shoot this run until it's all cases again. After this lot of 2000 is fired, won't use standard primers in this round ever again.
Chris

[Lead Fred]

Ive used CCI 34s for all my semis, and never have had a slam fire.
MRS Freds SKS tend to slam once and awhile, but we only shoot old milsurp out of it

[dg31872]

Thanks for your help. We have 450 and 41 primers. Use the 450 in 223 lever and bolt guns. The 41 in AR. I think that I will use the 41 in the carbine as well. The carbine is my wife's, and I don't want any surprises.

[Outpost75]

The base metal cup thickness of the military .30 carbine primer is 0.0185+0.0015-0.000 so in this respect, it compares to the Federal 200 or Remington 6-1/2, or the current 9mm military primer used in the M882, rather than the heavier cupped Remington 7-1/2, Federal 205 or military 5.56mm primers.

[Larry Gibson]

cwheel

Note that the slam fires, with CCI standard small rifle, happened with loading as a single round only, and never when feeding from a mag.

Suggest you might want to load the M1 Carbine as intended; from the magazine. I have seen the same firing pin dimple on milsurp 30 Carbine, 7.62 NATO, 5.56 NATO, 7.62x39, 7.62x54R, 8mm and '06 when loaded, even from the magazine, directly into the chamber on gas guns. The dimples were the same size on commercial primers. Some primers, even "milspec" (adopted well after a bajillion .30 Carbine, '06, 7.62 NATO, 5.56 NATO and other military cartridges were loaded and fired in gas guns) have been involved is similar slam fire incidents.

Not criticism here just a suggestion as most of us learned (some learned the hard way) "back in the day" of HP shooting with the M14 and M1 not to load a cartridge directly into the chamber during slow fire. To do so invites a slam fire whether or not "milspec" primers are used. BTW; I've used about 5K+ #34s now in 7.62 NATO in my M1As and 3K+ #43s in my M1 Carbines and ARs; they dimple just the same as do commercial WLRs and WSRs when loaded from the magazine and not fired.

Larry Gibson

[Outpost75]

The carbine, like the Garand and M14, has a cam in the receiver web which engages the "tail" at the rear of the firing pin. The purpose of this cam is to provide positive retraction of the firing pin so that the rifle cannot fire if the hammer is dropped with the bolt partially unlocked. During assembly a long dial indicator gage is inserted down the muzzle to measure the depth of firing pin retraction relative to the boltface. I'm not sure what the specification was on the carbine, but on the M1 Garand and M14, when a slave handle was used in which the bolt was rotated 7-1/2 degrees short of full lockup, the firing pin tip had to be at least flush with the boltface, in the maximum material condition of tolerance stacking, with the desired dimension being 0.005 below flush.

When you have guns being assembled with mixed parts, some of which could be rejects, which never gaged up properly in the first place, and when you have non-USGI parts put into the mix and the normal 100% gage checks normally required at the arsenals and depot rebuild are never performed, you suffer the fate of the blind monkey.

FWIW, Ruger built their own firing pin retraction gages for the Mini-14 series, under the direction of Albert Cole, a retired engineer from Springfield Armory, the REAL ONE, and it is a 100% check performed whenever a bolt or firing pin is fitted or replaced, either on new rifles, or in customer service. When I went through Ruger Armorers School in the 1980s, I found it refreshing to find government type gages in use, with which I was familiar, and their use being skillfully being taught by people who actually understood their importance.

[cwheel]

Thanks Larry, think you are correct here. Back in the day, the Navy didn't get much trigger time, not any HP match shooting either. Our time was spent passing the ammo and food to you folks on shore. I did the same experiment with my AR15's and got the same result after the slam fires in the carbines. That is a rifle ( the AR ) that doesn't lend itself to loading 1 round in the chamber and closing the bolt. Sure enough, same dent in the primer, no slam fire though. Have not given this a try in my old IHC yet, but I'll take your word for it. Still think next loading I'm going to the harder milspec primers in my autoloaders just for a higher comfort level. No more single round loading directly into the chamber though. Hope that by the time to load the next batch comes up, primers will be available again so I can buy some and give them a try.
Chris

[cwheel]

Outpost 75, I find the gage concept interesting. Yes, if all were done this way, would be difficult at best to have any slam fire. Must have been one heck of a long stem on that dial indicator. I have a Starrett AGD #3 with 5" of travel and thought that was long. Long indicators were used long before DRO's came into common use in industry. Winchester carbine #1 traces back to the DCM in the 60's, #2 is unknown. Could well have mismatched repair or rebuild parts. Both carbines have Winchester bolts, but that isn't saying they are original to the rifles. Think I'm going to just stick to loading from mags, and milspec primers, to eliminate future slam fires. Hope that harder primers gain a small margin of safety. Original gages would be nice to check, but I'm sure they are all long gone now.
Chris

[zomby woof]

I've used Magtech, CCI, Wichester, Fiocchi and Tula primers on several Carbines and never had had a slam fire. I suggest pulling apart the bolt and make sure it's clean.

From the 1942 basic M1 Carbine field manual. Single round loading.

To
OPERATE CARBINE AS SINGLE LOADER.
Making sure the receiver is empty, pull the operating slide to the rear and press down on the operating slide catch with the right thumb, locking the operating slide in its rear position. With the thumb and forefinger of the right hand, insert a single cartridge into the chamber. Pull back on the
operating slide handle and release it allowing the bolt to go forward

[cwheel]

Zomby woof, that is exactly what I did at the range when I had the slam fires. Both bolts were disassembled and checked, both were clean, free floating, and unlubed. With this lot of CCI standard small rifle primers, slam fire will happen when loaded that way as singles, about 1/20 rounds. Also note that the safety was on and the hammer never fell. Not going there again, from now on, loading from a mag no matter what the book says.
Chris

[zomby woof]

Zomby woof, that is exactly what I did at the range when I had the slam fires. Both bolts were disassembled and checked, both were clean, free floating, and unlubed. With this lot of CCI standard small rifle primers, slam fire will happen when loaded that way as singles, about 1/20 rounds. Also note that the safety was on and the hammer never fell. Not going there again, from now on, loading from a mag no matter what the book says.
Chris

Cwheel,
my only point was maybe something else is wrong, not the chamber loading. The rifle was designed to be single loaded into the chamber.

[Outpost75]

Sensitivity standards regarding the "drop ball" height for "all fire" vs. "none fire" for commercial vs. military primers are quite different.

[cwheel]

Zomby Woof, no offense taken at all. My 2 carbines are going to the grandkids and I'll do anything to make them as safe as I can with that in mind. One thing I've missed so far in their training was to teach never loading from anything except for the mag. Larry's comment backs this up as well. The OP asks about primers, and that takes us to my experience. Every post so far is constructive. After the slam fires, that was the next lesson they learned, only loading from the mags, and why.
Chris

[Chev. William]

Re: Carbine single load 'Slam Fires': Please have your two Carbines inspected for specification cam surface measurements on both the Receiver bridge and the Firing Pin. If the bolts are not known to have been properly fitted by the Government armory please have the head space checked/measured also. The design of the Carbine is such that 'Slam Fires' should be impossible IF all parts are assembled to specification measurements.
There are Commercial places that advertize an inspection service for M1 Carbines so you should be able to find a well qualified shop with the proper tools/gauges to properly do the required measurements.
Best Regards,
Chev. William

[Outpost75]

Outpost 75, I find the gage concept interesting. Yes, if all were done this way, would be difficult at best to have any slam fire. Must have been one heck of a long stem on that dial indicator. I have a Starrett AGD #3 with 5" of travel and thought that was long. Long indicators were used long before DRO's came into common use in industry. Winchester carbine #1 traces back to the DCM in the 60's, #2 is unknown. Could well have mismatched repair or rebuild parts. Both carbines have Winchester bolts, but that isn't saying they are original to the rifles. Think I'm going to just stick to loading from mags, and milspec primers, to eliminate future slam fires. Hope that harder primers gain a small margin of safety. Original gages would be nice to check, but I'm sure they are all long gone now.
Chris

Yes, it is a LONG probe on the dial indicator! But travel of the plunger was only 0.05". The ones at Ruger were by Starrett, modifying the boltface to muzzle measurement as needed, but otherwise following the aperture card microfilms from Springfield which dated from the WW2 era.

[bakrzdzn]

WOW, I love all the information that is passed on this forum. I have not had a slam fire yet...with my inland carbine, I don't think I have single loaded many rounds. I do see the dimple in unfired cases, i.e some one needs to go check targets so the range goes cold before you can shoot the round that just chambered. I mostly have used winchester sr primers. I bought a box of wolf primers, a while back, they are said to have a harder cup, like the cci mil-spec they had next to the wolfs. have not used the wolfs yet tho.

Roy

[dale2242]

I have never had a slam fire with an M1 carbine.
I have used most every brand of small rifle primers.
I never single load.
I always feed from the magazine.....dale