First time handloading for my 2 USGI warbabies. The bucket of once-fired brass is full. What is the preferred primer for this cartridge? Hodgdon says CCI 400. Lyman says Remington 6 1/2. Others have recommended CCI 41, WSR. I used CCI 41's in my initial batch of 100. Had two failures to fire, despite good looking pin strikes, one in either rifle. Haven't seen that with factory loads. Maybe they weren't seated quite deep enough. So what is your preferred primer, or do they all work just fine?
M1 Carbine primers
- Thread starter gatorwade
- Start date
- Status
Hypnogator
Member
I bought 1,000 CCI-41s for loading .223 for my ARs, and now regret having spent the extra money. No failures, but average velocities slightly below identical loads with CCI-400s.
The ONLY reason I would consider using 41s now would be that after ejecting a live cartridges from my Bushmaster, a slight dent is present on the primer, indicating that the firing pin is lightly hitting the primer when it goes to battery. CCI-41s are supposedly made heavier to prevent slam-fires.
That being said, I've never had a slam-fire with a CCI-400 primer (or any other primer) in this rifle.
IIWY, next range trip, I'd fire a round, then eject a live round, at least 10 times. If you see no evidence of the firing pin hitting the primer, then you can safely use CCI-400s.
FWIW, I use the 400s in all my .30 carbine loads.
The ONLY reason I would consider using 41s now would be that after ejecting a live cartridges from my Bushmaster, a slight dent is present on the primer, indicating that the firing pin is lightly hitting the primer when it goes to battery. CCI-41s are supposedly made heavier to prevent slam-fires.
That being said, I've never had a slam-fire with a CCI-400 primer (or any other primer) in this rifle.
IIWY, next range trip, I'd fire a round, then eject a live round, at least 10 times. If you see no evidence of the firing pin hitting the primer, then you can safely use CCI-400s.
FWIW, I use the 400s in all my .30 carbine loads.
ArchAngelCD
Member.
If you can afford them I feel the CCI #41 primers are the safest. I would not use Remington 6 1/2 primers for 30 Carbine ammo unless it was going to be fired in a handgun ONLY. The Remington 7 1/2 primers are rated for .223 ammo meant for a semi-auto so I'm comfortable with them in the 30 Carbine too. Like said above, I have never had a problem with CCI-400 primers in a semi-auto. I'm guessing that's because they are not as sensitive as most other primers. I also see no reason not to use CCI-550 primers. The 30 Carbine develops no more pressures than the .357 Magnum. From what I've read SRP and SPMP have the same cup thickness and the magnum pistol primer will burn hot enough to insure proper ignition.
USSR
Member
I have always used a standard SRP for the .30 Carbine. I am presently using Tula's. The .30 Carbine with it's light weight bolt and short bolt travel is not really conducive to slamfire issues. Just MHO.
Don
Don
I also use regular small rifle primers. What did everyone use before the advertising of Military 41 primers.??
The rifles are not full auto. Use them in my AR's also.
Hodgdon who sells H110 (one of THE major powders for the 30 carbine) use a CCI 400 SRP. Guess it's good enough for them.
The rifles are not full auto. Use them in my AR's also.
Hodgdon who sells H110 (one of THE major powders for the 30 carbine) use a CCI 400 SRP. Guess it's good enough for them.
Sunray
Member
CCI 41's are nothing more than magnum primers. Anything about 'em is marketing.
"...supposedly made heavier to prevent slam-fires..." Marketing. Slam fires are caused by improperly seated primers. Not the primer itself or the rifle.
Been using regular small rifle primers with IMR4227 and 110 grain bullets(HP's and FMJ's with no fuss) for 40 years. Makes a very satisfying BARK sound too.
"...supposedly made heavier to prevent slam-fires..." Marketing. Slam fires are caused by improperly seated primers. Not the primer itself or the rifle.
Been using regular small rifle primers with IMR4227 and 110 grain bullets(HP's and FMJ's with no fuss) for 40 years. Makes a very satisfying BARK sound too.
Sunray actually knows better about mil spec primers, for at least a decade he and a trio of other CCI haters have been disparaging CCI, CCI primers at another forum. Initially CCI was the only US manufacturer offering its mil spec primer line to the market and these guys denied slamfires happened, denied there was anything different about mil spec primers, and generally spread hate towards CCI. There is basically nothing I have said about primers that I have not posted in threads where he claims mil spec primers are a marketing gimmick.
This mechanism relies primarily on primer insensitivity to prevent an in battery or out of battery slamfire. Notice in the following photographs that the Garand type mechanism, which the M1 carbine uses, does not have a positive mechanical means of holding the firing pin back, instead the firing pin is entirely free floating through out most of its travel. There is contact with the firing pin retraction cam, but this is not positive nor does it completely retract the firing pin. This cam is there to break the firing pin out of the primer indent, if this did not happen the firing pin would likely break as the bolt rotates out of battery.
Bolt fully retracted
Firing pin just at retraction cam.
Firing Pin fully forward.
Bolt movement is not perfectly smooth. Slow motion pictures on the M14 mechanism reveal a lot of hesitations, vibrations, going on during bolt closure. Bolt bounce exists on other mechanisms, probably exists with this mechanism. Since there is virtually nothing preventing the firing pin from touching the primer during feed, and during the period when the lugs are not in engagement, it is prudent to use the least sensitive primers you can in these mechanisms.
Whenever a firing pin rebounds off a primer there exists the chance of ignition. This is due to the fact that the energy to ignite a primer varies considerable within a lot. Primers can be made to be more or less sensitive, and if you think about it, what can be done is rather obvious. Firstly, the primer mix can be adjusted to make primer cake more or less sensitive. Primer cups can be made thicker, or harder. Anvil angle can be adjusted to be stiff or somewhat “cushion” the blow.
I don’t know if the #41 primer is the proper primer for a M1 Carbine. In the old primer spec Mil-P-46610E “Primers, Percussion for Small Arms Ammunition” the M1 carbine primer is the least sensitive primer out of all military primers, including the later #41 primer. This was because the M1 Carbine was the first of its kind and the primers could be made very insensitive as there were no other mechanisms using the same cartridge.
A history lesson of a sort, the early M1 Garand had a round firing pin exactly like the M1 carbine firing pin. These are pictures of the rare early round firing pins, when Orion 7 had them, they sold out their inventory at $100.00 apiece!
Obviously the Army experienced slamfires in early Garands because the later firing pin was scalloped to reduce weight. On top is the Garand firing pin, the middle the M14, and the bottom a M1 Carbine firing pin.
Making the primer insensitive for the Garand would have likely caused misfires in other mechanisms which used the 30-06 cartridge. The simplest solution was to reduce the kinetic impact energy of the Garand firing pin by reducing its weight. This was not necessary for the M1 carbine, so they kept the relatively simple to make but heavy, round firing pin. To accommodate this heavy firing pin, the M1 carbine primer spec is the least sensitive of all military primers.
The history of the #41 primer is different and came about due to slamfires in the early M16’s.
http://www.dtic.mil/dtic/
Report of the M16 Rifle Review Panel. Volume 5, Appendix 4. Ammunition Development Program
Primer Sensitivity
Initial Specifications. Ammunition specifications established by the Air Force on 24 January 1963 provided for quality control against cocked, inverted, loose, and nicked primers. The specifications further provided for inspection and test of waterproofing and the crimp of primers. However, the specifications did not provide for specific limitations on primer sensitivity for 5.56mm ammunition.-
Development. At the first meeting of the Technical Coordinating Committee on 26 March 1963,16 / the Air Force representatives submitted a list of reported ammunition deficiencies, which included "high primers" and "primers too sensitive". It was agreed that Frankford Arsenal would investigate the matter and recommend corrective action.
One of the malfunctions reported by the Air Force was the premature firing of cartridges that occurred upon initial charging of the M16 rifle with a cartridge from the magazine, or upon singleloading of a cartridge directly into the chamber, or when two rounds were fired at one trigger pull during semiautomatic fire.
This malfunction was attributed to "high" or protruding primers, although the tests did not confirm this theory..
However, analysis indicates that if high primers caused the premature firing, the firing should have occurred upon impact of the bolt face with the protruding primer. At this point in the weapon cycle, the bolt head would not. have been rotated to the locked position by action of the cam pin and carrier. Had firing occurred with the bolt in the unlocked position, it would have resulted in a blow back and would not have been undetected. No such disruptions were reported-. Since premature firing occurred after bolt-locking, it must have coincided in time with the impact of the bolt carrier against the bolt head. At the instant of impact, the "free floating" firing pin is moving at the velocity of the bolt carrier. The kinetic energy of the pin must be dissipated by such frictional forces as it encounters in the forward movement, and, finally, in impact of the firing pin tip with the primer of the chambered cartridge. This premise was confirmed by the visible indentation appearing on cartridges which were chambered by the mechanism and extracted unfired.
Frankford Arsenal identified test procedures for measuring firing pin energy and recommended limits for primer sensitivity.
Remington Arms Company, on the basis of the information contained in the Frankford Arsenal First Memo Report, undertook the design of a new primer that would be less sensitive and less susceptible to the inadvertent energy delivered to the primer by the free-floating firing pin of the AR15 rifle. Since it is difficult to adjust primer sensitivity by chemical changes, Remington elected to accomplish the desensitization" by increasing the mechanical strength of the brass primer cup, which must be indented by the firing pin to cause ignition.
As a result of the decision of the Commanding General, USAIIC, to modify the rifle, Colt's Inc. developed two designs, a linear spring device and a cam pin friction device, to reduce firing pin energy on bolt closure. These two designs were tested by the Air Force conclusions of this test were that both devices effectively reduced firing pin energy; however, the Air Force recommended against their adoption because they increased the probability of a misfire (although no failures to fire were identified in the test results), added to the cost of the weapon, and adversely affected its reliability. Army tests of these devices indicated that the linear - ~spring friction device was a satisfactory solution; however, at the Technical Coordinating Committee meeting of 10 December 1963, at which a comparison of all tests done by the Army, Air Force, and Colt's Inc. was made, the committee agreed to adopt a modified lighter firing pin, which was used in the cam friction device and was recommended by Colt's as a solution to the problem..
So, to reduce slamfire rates in the M16 the Army did two things: 1) it reduced firing pin weight, and 2) required the use of less sensitive primer, the #41 primer.
The heavy original M16 firing pin on top.
All ammunition makers in the US make “mil spec” primers for US military contracts. To date, only Federal and CCI offer their military product line to the public. All primer manufacturers should be encouraged to do so. Wideners’ sold Wolf primers, part # KVB223M, as an military small rifle primer. https://www.wideners.com/itemdetail.cfm?item_id=8975 Good luck on finding any of them.
http://bulletin.accurateshooter.com/2011/09/new-federal-gold-medal-match-primers-for-ars/
CCi
September 11th, 2011
New Federal Gold Medal Match Primers for ARs
Federal Ammunition has released a new type of small rifle match primer optimized for AR15s and similar semi-automatic rifles. The new Gold Medal® AR Match Primers, designated GM205MAR, have harder primer cups than the popular Federal 205M match primers. The harder cup is designed to perform better in semi-automatic actions that use free-floating firing pins. A Federal spokesman said that Federal’s “normal” 205M primers were not ideal for use in firearms, such as ARs, with free floating firing pins. Hence Federal designed the new GM205MAR primers. These are available now from major vendors such as Midsouth Shooters Supply, which offers the new GM205MAR primers for $35.22 per thousand.
Here's the skinny on the Federal GM205MAR primer.
http://68forums.com/forums/showthread.php?32572-Here-s-the-skinny-on-the-Federal-GM205MAR-primer
Slamfire risks are real, this is a picture of the after effects of an out of battery slamfire in an M1a.
As an idea of slamfire rate, I only have this data, which is on the M14. I have a paper copy of this report. The Army was testing production models of H&R’s and using SA M14’s as control specimens. Six rifles were under test, three by HRA and three by SA. All rifles were gaged for dimensional part compliance, and part interchangeability. Such things as the thickness of the chrome coatings were measured, etc. After gauging the rifles were reassembled and underwent endurance testing which was each rifle was to fire 6000 rounds. The total amount of 7.62 Nato to be fired would have been 36,000 rounds.
USATECOM Project No 8F-3002-04, Comparison Test of rifles, 7.62 MM, M14 Manufactured by Springfield Armory and Harrington and Richardson Arms Company. Author G. E. Hendricks, July 1963.
At round 5271 a Springfield Armory M14 went off out of battery. The report states:
So, six rifles were tested, five completed the test firing 6000 rounds each, one slamfired out of battery at round 5271, for a total round count of 35, 271. Therefore a crude estimate for the probability of an out of battery slamfire, with mil spec primers, is 1:35,000. You can expect that with less sensitive commercial primers, the out of battery slamfire risk would be higher, by what, who knows?
Springfield Armory warns about the increased chance of a slamfire with commercial primers in every manual sent out with a M1a:
Springfield Armory M1A Manual, page 4
www.springfield-armory.com/download.php?asset=M1AManual.pdf
Ammunition
I recommend using the least sensitive primers in this mechanism, and regardless of the primer you use, never assume the gun won’t slamfire in battery, or out of battery. Don’t chamber a round with the muzzle every pointing at something you don’t want to put a hole in!
You can find a number of out of battery slamfire reports on the M1 carbine, you just have to search.
Out of battery Slamfire in M1 Carbine with Federal American Eagle Ammunition.
http://www.thegunzone.com/ij-m1carbine_kb.html#nb2
http://thefiringline.com/forums/showthread.php?t=455111
Witnessed 'powder burn' at the range today
Sunray knows all of this, and this is the most distasteful part of reading his posts: what sort of mind could knowingly give advice which will hurt or cause injury to another person?
CoalTrain49
Member
I'm using CCI 450 mag primers and get a few FTF's every 100. I attribute this to hard primers. I couldn't find 400's for a long time and just loaded up on 450's when I found them. My load is 12 grns of Acc#9 with 110 FMJ bullets. I called a tech at Accurate and he said the load was fine. My feeling is you don't need mag or mil spec primers with an M1 USGI carbine. The 400 will work just fine. When you hear about slam fires with an M1 carbine it's usually a Universal and not a USGI. If your brass is trimmed to the proper length, <1.29 you won't have a slam fire with a USGI carbine unless you have a head space problem. That means a bolt won't close on a 1.29" case and that's easy to check. Slam fires are caused by head space problems. I trim to 1.28" because the the brass always grows.
I have 2 USGI carbines and load everything I shoot. Good luck with your new adventure.
I have 2 USGI carbines and load everything I shoot. Good luck with your new adventure.
HOWARD J
Member
I have an m1 carbine by Iver Johnson
I use CCI-400 primers & have for many years
When I let the bolt fly it does leave a dimple on the primer----it never has fired from that
I use CCI-400 primers & have for many years
When I let the bolt fly it does leave a dimple on the primer----it never has fired from that
jcwit
member
Just a thought.
Is that is as in "yet"?
Is that is as in "yet"?
CoalTrain49
Member
Releasing the slide from the locked open position using a mag is the proper way to chamber a round. The reason that he has never had a slam fire is the bolt picks up the round from the mag and both bolt and round travel to the chamber together. The FP doesn't have enough pressure by itself to detonate a primer. Some larger caliber weapons do and that was the reason for mil spec primers. You don't need those in an M1 carbine. If you are concerned about floating FP strikes go to mag or mil spec primers but I will assure you that you will start seeing FTF's because the primers are too hard. Some like the built in security of hard primers but the trade off is FTF's. Sometimes chambering a round without a mag and letting the bolt gently close on the round will result in the bolt not closing and locking. Don't do that. The M1 carbine was not designed to do that.
Last edited:
Really? Is this true for all weapons or just the M1 carbine?. And how did you determine that the carbine firing pin does not have “enough pressure” to “detonate a primer”?
The military specified a primer sensitivity for all their weapons, but the M1 carbine used primers that look to be the least sensitive of all primers used in military small arms. Why was that?
Magnum primers don't necessarily have mil spec insensitivity. Mil Spec primers are supposed to be magnum in terms of ignition energy, (and in the main, I believe that) but that does not mean magnum primers have harder cups, or other design features to reduce sensitivity. There is a tradeoff, primer insensitivity versus ignition reliablity. I believe this is the number one reason commercial primers are so sensitive: misfires. There are literally millions of firearms that are not maintained, dirty, and have old and weak mainsprings. Ammunition companies got tired of receiving complaints about their ammunition not going bang and I believe over time, they continued to make their primers more and more sensitive. They even claim this as a quality attribute. There is little to no liability for them as shooters don’t sue if their rifle slamfires or slamfires out of battery.
However, if anyone has misfires with military primers in a military weapon, it is about time to buy a new mainspring and clean out the firing pin recess in their bolt.
I am very particular about replacing old mainsprings with new. Decades ago I saw effects on target with old military mainsprings. Group sizes decreased when I put in a new, full strength mainspring. Many ignition systems are so poorly designed that they have marginal ignition strength even when new. This is an excellent read on this problem: IT DON’T GO BANG:FIRES, HANGFIRES, MISFIRES AND SHORT ORDER COOKS IN JERSEY By Mark Humphreville http://riflemansjournal.blogspot.com/2009/08/primers-it-dont-go-bang.html
I have had, and others have experienced, misfires in cold weather with the CMP Kimbers. Idiots within the Government Arsenal system removed the bolts out of the weapon, which kept the mainsprings compressed for 30 years, and even then, the Kimber M82 Government rimfire does not have a surplus of ignition energy. Replacing the old, weak mainspring, brought ignition to 100% in cold weather.
jcwit
member
And I can assure you that you are wrong, at least in the 2 U.S. Carbines I shoot my own reloads in.
HOWARD J
Member
I have been shooting this carbine for about 35 years
I have never seen any "yet"
BTW: this is my home defense weapon--it gets test fired quite a bit
I have never seen any "yet"
BTW: this is my home defense weapon--it gets test fired quite a bit
Last edited:
jcwit
member
That's good.
One of my carbines I purchased back in the mid 60's, so I have been shooting it for 50 years next year. A couple of years ago I shot over 2,000 rounds thru it, so I too am fairly familiar with it.
My primary home defense weapons depend on what room I'm in at the present.
Beside me at present on the end table is a CZ 70, in my dining room on the hutch behind my chair is a Makarov, in the bookcase beside my bed is a Kimber, a SCCY 9mm, and in my shop is a Springfield 45. All are loaded with 1 in the tube.
jcwit
member
As far as "never seeing any Yet", neither did A.J. Foyt, till he hit the wall at Indy at age 50+.
You walk in the pasture long enough you WILL eventually step in it.
Last edited:
HOWARD J
Member
A slam fire will not bother me as I always keep my rifle pointed in a safe direction.
NOW: an open bolt firing might shake me up----I try to keep my weapon clean.
AND HERE-- I thought I was the only crazy around.
Shop: Ruger 45
Living room: 1911 45
Bedroom: M1 carbine
Garage: Glock 9MM
NOW: an open bolt firing might shake me up----I try to keep my weapon clean.
AND HERE-- I thought I was the only crazy around.
Shop: Ruger 45
Living room: 1911 45
Bedroom: M1 carbine
Garage: Glock 9MM
Last edited:
jcwit
member
Not crazy, just Prepared!
I did have a slam fire once, it was with an SKS, yes It was pointed down range ant not in the air, yes it was clean, even the bolt. It also has a free floating firing pin, there is a spring kit available to use as a mod to eliminate this potential problem in the SKS.
I did have a slam fire once, it was with an SKS, yes It was pointed down range ant not in the air, yes it was clean, even the bolt. It also has a free floating firing pin, there is a spring kit available to use as a mod to eliminate this potential problem in the SKS.
HOWARD J
Member
@jcwit
Where can I get a spring kit for my 2 SKS's
Thanks
H
Where can I get a spring kit for my 2 SKS's
Thanks
H
Reloadron
Contributing Member
At 64 years old I began shooting at around 8 years old and hand loading when I was around 22 years old. So for what it may or may not be worth I have been hand loading for about 42 years.
When I choose a primer I try to choose it for the rifle I am loading for.
All of the above are obviously small rifle primers. I should also have a few additional flavors around here. For loading M1 Carbine I go with the CCI #41. I haven't always done that. I have also used CCI #400 (pre CCI #41) and a host of others. Do the CCI #41 primers really prevent a slamfire, especially in a rifle using a small and light free floating firing pin? Beats the hell out of me but they do work. My carbine likes them and why tempt fate? They have yet to give me a failure to fire or in the case of a primer failure to detonate.
Failure to detonate in the case of a hand load primer can have a number of causes including but not limited to a worn firing pin, an incorrectly seated primer, a worn firing mechanism in the rifle and other rifle issues. When seating a few hundred primers it becomes easy to have a few not get seated correctly and bottom out in the primer pocket.
Anyway, when loading for my AR rifles or my M1 Carbine I use the CCI #41 primers or look for a less sensitive primer. Works for me anyway. When loading for my bolt gun in 223 any of the 4 pictured seem to do just fine. Why tempt fate when there isn't a need to?
On a side note, regarding the post by Slamfire. When it comes to priming issues or slamfire issues (as in actual slamfires) I enjoy his post. Slamfire takes the time to add supporting material to his post. He defines why he post what he post and that counts.
Just My Take....
Ron
When I choose a primer I try to choose it for the rifle I am loading for.
All of the above are obviously small rifle primers. I should also have a few additional flavors around here. For loading M1 Carbine I go with the CCI #41. I haven't always done that. I have also used CCI #400 (pre CCI #41) and a host of others. Do the CCI #41 primers really prevent a slamfire, especially in a rifle using a small and light free floating firing pin? Beats the hell out of me but they do work. My carbine likes them and why tempt fate? They have yet to give me a failure to fire or in the case of a primer failure to detonate.
Failure to detonate in the case of a hand load primer can have a number of causes including but not limited to a worn firing pin, an incorrectly seated primer, a worn firing mechanism in the rifle and other rifle issues. When seating a few hundred primers it becomes easy to have a few not get seated correctly and bottom out in the primer pocket.
Anyway, when loading for my AR rifles or my M1 Carbine I use the CCI #41 primers or look for a less sensitive primer. Works for me anyway. When loading for my bolt gun in 223 any of the 4 pictured seem to do just fine. Why tempt fate when there isn't a need to?
On a side note, regarding the post by Slamfire. When it comes to priming issues or slamfire issues (as in actual slamfires) I enjoy his post. Slamfire takes the time to add supporting material to his post. He defines why he post what he post and that counts.
Just My Take....
Ron
Reloadron
Contributing Member
Give this link a read.
There are other just spring kits but Murray's deals with the SKS firing pin.
Ron
ArchAngelCD
Member.
All I can say, I do not know if a CCI #41 primer is absolutely necessary for all semi-auto ammo but like I said above, if you can get them why not use them? "Better safe than sorry" comes to mind. I have used CCI #41, Rem 7 1/5, CCI-400, CCI-450 and WSR primers in .223 ammo I loaded for an AR-15. Thankfully none were a problem and I only used the win primers because it was all I could find.
I feel perfectly safe using (in this order) CCI #41 primers, CCI-450 primers and then CCI-400 primers in my .223 ammo. The CCI primers in general seem to be less sensitive than any other company's primers.
I feel perfectly safe using (in this order) CCI #41 primers, CCI-450 primers and then CCI-400 primers in my .223 ammo. The CCI primers in general seem to be less sensitive than any other company's primers.
jcwit
member
Howard, Ron beat me to it, yes that is the site.
- Status
