Small Rifle primers in 357 mag

[Cheap Trick]

My son bought a revolver about 15 years ago and I used to load all of his 357 and 38 ammo with small rifle primers since this is what I had during the Obama ammunition component drought.
Now I am reloading for my own revolver, I have been reloading 38 Specials with small pistol primers, OK so far, today I loaded up a couple of magnums with 13.5 grains of 2400, 158 grain powder coated boolets, and small rifle primers. the cylinder locked up after the last one. I'm assuming that the load is too hot with the rifle primers and will back off a grain and try again.
any thoughts?

[kayala]

That’s probably a typo and bullet is 158 gr ? How did cylinder locked up, could it be no powder charge and bullet stuck in the forcing cone ? With 158 gr I wouldn’t consider 13.5 gr of 2400 super hot load.

[racepres]

That’s probably a typo and bullet is 158 gr ? How did cylinder locked up, could it be no powder charge and bullet stuck in the forcing cone ? With 158 gr I wouldn’t consider 13.5 gr of 2400 super hot load.
Indeed...just a good load.. 14.0 gr is 1130 to 1150 fps in my 4" DW..
I do Not have any problem using SRP or SPP. interchangeably...tho I generally use SRP, in place of SPMag primers...and Not Rem 6-1/2's either..too Soft Cup!!
During the last shortage ...everything got Rem 6-1/2's that wasn't over 1000FPS..Only a Fairly highly tuned S&W, with a decidedly smooth, light, trigger was a Problem...but it was problematic with Mag pistol primers...Worked best with Federal SPP.. finicky bugger went down the road!!!

[Delkal]

There is very little difference (if any) energy wise between a small pistol magnum and small rifle primers. I doubt substituting a rifle primer suddenly over pressured a moderate load. The only significant difference is the rifle primers have a thicker cup and can be harder to set off.

[relics6165]

Supposedly, small rifle primers and small pistol magnum primers are close to the same, if not identical. I wouldn't think it was the primer that locked up your revolver. But, all I can say for sure is that lots of people have been interchanging SPP and SRP for a while now due to the shortages that are now easing.

[racepres]

There is very little difference (if any) energy wise between a small pistol magnum and small rifle primers. I doubt substituting a rifle primer suddenly over pressured a moderate load. The only significant difference is the rifle primers have a thicker cup and can be harder to set off.

Except Remington 6-1/2's...they are fragile cups truly..I'm warnin ya!!!Stay at lower Pressures with them...like Remington Advises!!!

[Cheap Trick]

S&W 66-1
Big kapow not just a primer, and I did open the cylinder, by holding the release and popping the side of the cylinder with a rubber mallet that I happened to have with me. I could not push the two empties out with finger pressure, I used the mallet.
Yeah, I saw the 258 grain mistake and immediately amended to 158 grain.

[kayala]

S&W 66-1
Big kapow not just a primer, and I did open the cylinder, by holding the release and popping the side of the cylinder with a rubber mallet that I happened to have with me. I could not push the two empties out with finger pressure, I used the mallet.
Yeah, I saw the 258 grain mistake and immediately amended to 158 grain.
Powder overcharge maybe, as many said above SRP is pretty much same as SPM energy wise. I'd look elsewhere for a problem. Was that a big batch you've loaded, did you try to pull few rounds to check powder charge ?
an edit: do you have a picture of the primers from the empties you had to knock off ?

[Cheap Trick]

Actually, I was trying to find a load and only loaded two, I weighed each one out with my RCBS 5-10 and visually verified the same height of propellant.
The primers were somewhat flat as I expect magnum loads to be. one was marginally cratered. I assume that was the problem, but I have been reloading since 1981 and have seen really cratered primers before. One bullet was deeper than the other due to adjusting the dies from 38 to 357, I suspect that this made the one primer crater.

[racepres]

Actually, I was trying to find a load and only loaded two, I weighed each one out with my RCBS 5-10 and visually verified the same height of propellant.
The primers were somewhat flat as I expect magnum loads to be. one was marginally cratered. I assume that was the problem, but I have been reloading since 1981 and have seen really cratered primers before. One bullet was deeper than the other due to adjusting the dies from 38 to 357, I suspect that this made the one primer crater.

If it was seated much deeper....it certainly would cause over pressure.. Seating Depth is Very Important...

[NSB]

I shoot more 357mag loads than probably 98% of the people on here. I’ve been using small rifle primers for years with many different loads and have had ZER0 problems. One caveat: I don’t load to maximum loads or beyond. No need to. I load a lot of H110 and WW296 loads up to book specs and have had no problems at all. If you had to pound cases out of your gun it’s because you used mag cases without cleaning the chambers after shooting 38spl cases (crud ring) or you used the wrong powder. It’s not the primer.

[Larry Gibson]

I’ve no idea who came up with the idea that pistol magnum primers and rifle primers have the same “energy”. What magnum primers have different from standard primers is a different primer compound that produces a different intensity of brisance (not exactly a correct term but is commonly used to describe primer intensity). That different intensity can, and does, alter the time pressure curves of slower burning powders. How much depends on the primer and the deterrents [the deterrents are what determines the burn rate] of the specific powder.

As we see from this test of 6 different small pistol primers in the 357 Magnum cartridge there can be was close to 7,000 psi difference between the WSP primers and the WSPM primer with this load of the 358156 over 14 gr of Alliant 2400. The substitution of the WSPM primer took the psi from just under the SAAMI MAP to well over the MAP. So, if we were to assume (Ido not BTW) that a SRM primer can be the same as a SPM primer then the test results demonstrate a large increase in pressure can occur.


---Primer---------Powder----- Velocity----SD/ES-------PSI-----------SD/ES---------Group

Federal 100--------H2400--------1425-------13/44-------31,000-------1500/4500-------5.45”
----------------------A2400--------1572-------16/46-------38,400-------1200/4000-------5.1”

CCI 500-----------H2400---------1452-------12/41-------29,200-------1800/5200-------4.95”
----------------------A2400--------1551-------15/39-------35,400-------1500/5100--------4.87”

Win WSP---------H2400---------1425-------16/60-------26,200-------2000/6900--------5.2”
---------------------A2400---------1536-------14/49-------34,800-------1200/4300--------3.75”

Federal 200------H2400----------1481-------11/38-------32,100-------2500/6600--------3.7”
Magnum---------A2400----------1566-------15/46-------38,900-------2000/5800--------3.15”

CCI 550----------H2400----------1457-------11/37-------30,300-------2500/8900--------3.6”
Magnum----------A2400----------1581-------17/51-------39,000-------2100/6400-------3.55”

Winchester-------H2400----------1446-------22/67-------39,500-------2300/7000-------3.9”
WSPM------------A2400----------1607-------12/37-------41,600-------2700/9000-------2.85”

So what happens if we use a small rifle primer? Well I didn’t test that 2400 357 load specifically with rifle primers but I have tested large rifle primers in the 44 Magnum with Alliant 2400.

Alliant 2400 load; 44-250-K over 21 gr Alliant 2400
Control load;
Fed 150/1542/18/51/30,800/1,000/2,700

LR primer loads;
Rem 9 1/2/1603/13/37/34,700/500/1,200
CCI 200/1589/20/46/33,000/1,800/5,000
CCI #34/1634/10/27/37,900/1,900/5,500
WLR/1633/8/22/37,600/1,000/2,600
Fed 215/1641/13/29/41,200/1,900/4,100

As we see, all of the rifle primed loads showed a considerable pressure increase over the control load which used a Federal LP Magnum primer. There was almost 11,00 psi increase.

Note; the increases in velocity seemingly do not really indicate the increases in pressure.

Yes, with some powders in some pistol cartridges such as the 9mm the substitution of a rifle primer for a pistol primer doesn't make much difference, especially with small charges of fast burning powders. However, with slower burning powders intended for higher performance loads in the magnum size pistol cartridges the use of a rifle primer can and most often does result in a large increase in pressure w/o a large increase in velocity.

It is apparent the OP found this out.

[Bowdrie]

The above post by Larry Gibson is a word to the wise.
Another thing to be aware of is that using small charges of slow powder can result in detonation.
The slow powders like to burn in a column from back of case to front.
When little charges of slow stuff are used the powder has a tendency to just "lay in a long trough", so to speak, and the primer flash goes across the whole length of the charge all at once.
This can cause very rapid pressure spikes.
It's not an "always" thing, but it does happen.

[racepres]

Actually, I was trying to find a load and only loaded two, I weighed each one out with my RCBS 5-10 and visually verified the same height of propellant.
The primers were somewhat flat as I expect magnum loads to be. one was marginally cratered. I assume that was the problem, but I have been reloading since 1981 and have seen really cratered primers before. One bullet was deeper than the other due to adjusting the dies from 38 to 357, I suspect that this made the one primer crater.

I'm sticking with Boolit seated too deep on this one!!!

[Bazoo]

If you only loaded 2 rounds in the cylinder, that could have locked it up. When only 1 or 2 rounds are loaded, the cylinder doesn't have even support during recoil.

My Blackhawk will do the same thing if I load only 1.

Thank you Larry for sharing.

[racepres]

If you only loaded 2 rounds in the cylinder, that could have locked it up. When only 1 or 2 rounds are loaded, the cylinder doesn't have even support during recoil.

My Blackhawk will do the same thing if I load only 1.

Thank you Larry for sharing.

Very interesting indeed.. so just empty brass makes a difference?? I have Never tested that but...seems strange indeed...

[Cheap Trick]

Thank you Gents,
You all have contributed to my understanding of what occurred. I know with "Cast Boolet" forum we get respectful, knowledgeable replies.

[Bazoo]

Very interesting indeed.. so just empty brass makes a difference?? I have Never tested that but...seems strange indeed...

Yes, empty brass keeps the cylinder from binding during recoil.

I first noticed it one day when I had only 1 round left out of a batch and I shot it on an unloaded cylinder. It bound up. So I started messing with it. I had never fired the gun without a fully loaded cylinder before that.

[Forrest r]

FWIW:

I'm pushing a 170gr MiHec 359-640 fn 1200fps in a snubnosed 586 (fn bullet on right).
https://i.imgur.com/Gyl21QA.jpg

170gr fn 14.7gr 2400 s&b small rifle primer. I use the same primer in my ar's.

No sticky extraction, no cratered primers, all 7 empty cases drop out time after time after time.

[georgerkahn]

My son bought a revolver about 15 years ago and I used to load all of his 357 and 38 ammo with small rifle primers since this is what I had during the Obama ammunition component drought.
Now I am reloading for my own revolver, I have been reloading 38 Specials with small pistol primers, OK so far, today I loaded up a couple of magnums with 13.5 grains of 2400, 158 grain powder coated boolets, and small rifle primers. the cylinder locked up after the last one. I'm assuming that the load is too hot with the rifle primers and will back off a grain and try again.
any thoughts?

Just as a note which may be germane? Some years ago I sought -- almost impossible to find at the time -- some 10mm Auto brass, and chanced upon a bag of 100 at a local gun show. I was super-happy, 'though the price was no bargain. After I tumble-cleaned and sized them, they looked OK, but when I went to put in new primers, they just about dropped in -- NO friction hold hardly at all. Well, (stupid George) I still loaded a block of fifty, and I was pleased -- at range -- to have made quite an array of yellow confetti from the Yellow Pages 'phone book which was my target! BUT, that sixth round locked the cylinder! I got lucky as a saged friend at range cleared it for me -- BUT -- the second or third round of next cylinder did the same thing!
With several live rounds still in the (it was a S&W Model 610) handgun, this was cleared with the help of a ($$$) gunsmith. I never loaded the un-tried fifty, and took apart the forty-something I had not yet tried to shoot. Bion, I did use the removed primers with zero difficulties; and, trashed the brass :(.
Just a thought -- your load may have nothing to do with your challenge -- it, hey, MIGHT be a loose primer pocket?
geo

[racepres]

Just a thought -- your load may have nothing to do with your challenge -- it, hey, MIGHT be a loose primer pocket?
geo
That is absolutely a Likely Scenario... Why no one else thought of that??? In General, I have certainly had Hard Extraction, (usually, but not always, over pressure), without other cylinder difficulties!! And, if normal extraction after the cylinder is open.... we have a Bingo!!! IMO

[Jtarm]

Except Remington 6-1/2's...they are fragile cups truly..I'm warnin ya!!!Stay at lower Pressures with them...like Remington Advises!!!

5 1/2s, which are SPP, are hard as freakin diamonds.

[kayala]

Another thought - if you've used once fired brass that was made for Hornady FTX bullet - it is shorter than normal, so pressure will be higher.

[racepres]

5 1/2s, which are SPP, are hard as freakin diamonds.

Huh...I have used thousands of 5-1/2's..No ignition problems and No Pierced Primers..Since I do Not use Primer appearance as a Pressure indicator..I have No opinion on toughness of the Cup of a 5-1/2... but the 221 Fireball has never had on pierce...Unlike the 6-1/2 cup which is fairly easily Pierced/Ruptured..
Curious what prompted the statement that 5-1/2's are Hard Cups??

[Delkal]

Would this idea work to clear a jammed cylinder from a loose primer pocket? Put an appropriate sized rod down the barrel till it hits the bottom of the case then give it some taps with a hammer? Unless the blown primer is mushroomed it seems like it would reseat easily.

[Jellyroll]

I use sr primers in anything that calls for a sp. Makes stocking up much easier.

[Loudenboomer]

Don't go off label. Good advice from many above. That being said, CCI says their small pistol magnum and their std. small rifle primer are the same primer.

[35 Rem]

May not have anything to do with this revolver locking up but I had a 38 Special that would lock up at random quite often. Finally figured out it was the shape of the firing pin. Rather than having a nice round nose that would retract from the fired primer easily, it had a square and even somewhat mushroomed shape that would grip the primer dent and hang on. Result was a locked cylinder. And of course, you can't see the firing pin with cylinder installed and brass present, so it took some time to figure out. Fix was to take firing pin out and spin it in a Dremel tool and reshape the nose with an emery board.