357 Max - SB1 - What Primer?

[bikerbeans]

Hi All,

Most of the published load data I found for the 357 Max is a for a revolver.  I searched and found rifle loads by a number of different individuals and for a number of different guns, H&R, Ruger, Encore etc.  There doesn't seem to be agreement on primers, folks are using SP Mag, SR and SR Mag.  Any thoughts on this?  My particular SB1 really dents the SP and SP Mag primers on the 38 and 357 Mag rounds I put through it.

BB

[OR-E-Gun Bill]

I've been using CCI 450 SRM in mine without any problems.



Bill

[dave29]

CCI 450 here as well.

[randy_68]

I tried CCI 450 and Rem 7 1/2 sr but had a lot of misfires even after changing to a Wolf xtra power spring. I switched to Federal SR and have not had a problem. They always go bang now.

[quickdtoo]

Maybe this will help with primer selection, they aren't all equal.

Tim

http://www.jamescalhoon.com/primers_and_pressure.php

[OR-E-Gun Bill]

I guess I should mention that my 357 SB1 is an Ilion made CAC and the firing pin is the same size as my SB2 frames.
Were some of the 357 SB1 frames made with the larger firing pins?


Bill

[quickdtoo]

H&R has been fitting 357mag barrels to SB1 frames for about 18months now, so there are lots on SB1 shotgun framed 357mags with large firing pins too, there have been some 357mags with pin related problems, easily solved with a change in primers, a little tougher to do when shooting factory ammo tho. I had pierced primers on my first Maxi on an SB1 frame using Dan Wesson factory ammo.  Worked fine on an SB2 frame tho. The same SB1(TDC) frame worked with no problems with a 30-30 barrel even, thicker primer cups in the 30-30 rifle primers, ya know. 

Tim

[PawPaw]

Maybe this will help with primer selection, they aren't all equal.

Tim

http://www.jamescalhoon.com/primers_and_pressure.php

That 's true, Tim.  But I've always considered the phrase "small pistol magnum" to be an oxymoron.  Pistol powder isn't that hard to light.

[quickdtoo]

Calhoun doesn't list pistol primers, but I suspect the mag pistol primers have thicker cups like small rifle mag primers which makes the difference, has nothing to do with how hot the primers are.  

Tim

[bikerbeans]

My Max is a "CAC" Illion SB1.  Loaded up 30 rounds with H110 and 180 grain XTPs (couldn't find the ssps, locally).  15 rounds with Fed SP Mag and 15 rounds with CCI 450s.  Will see how it goes.  I guess my only real concern is rupturing the primers as the firing pin on this gun leaves a major league dent in the primers.  To date I have only shot relatively slow pistol loads (38 & 357 mag) so tomorrow we shall see.  Maybe wear my welding helmet?

Thanks everyone for your input/suggestions.

BB

[tacklebury]

Honestly, it affects all three items, heat of primer, height of cup and thickness of cup.  Per CCI's description:

http://www.cci-ammunition.com/products/primers/primers.aspx?id=29

Their magnums are 23% hotter and about 10% thicker to withstand the higher pressures.  If firing moderate loads, Magnums can cause early bullet dislodging and fragmentation of your powder burn, ie. it will still be burning inside your rifling instead of in the brass.    That is my understanding at least.  I only use magnum primers with powders like H-110 which are harder to light or on heavier colt loads.  I made the mistake of grabbing some magnums once and was trying to get them to seat in some .45 acp ammo I had loaded, and noticed I was having issues getting the primer to seat fully.  Luckily, this clued me in and I was able to avoid possible pressure issues.  In smaller case capacities this can generate a much higher pressure spike.  That is why acp ammo has a shallower seat as compared to my .45 Colt brass which easily accepts the magnums.

[OR-E-Gun Bill]

The top three in the picture are mine using the CCI 450 primers.
The other nine are pictures of one of the other members here who was having trouble with his primers cratering with different types & brands of primers. I can't remember which frame he was using. The bottom three I believe were CCI 450 primers.



Bill

[quickdtoo]

Excess headspace plays a roll in cratering I believe,  and 357Mags seem to have plenty of headspace with their deep rim cuts, at least all that I've worked on have including both of mine. If you can shim the extractor out to hold the round against the standing breech, I think those craters will cease to happen.

Tim

[bikerbeans]

I shot my 357 Max for the first time this morning.

Loaded 15 rounds with 180 grain HPs, H110 17 to 21 grains with Fed Mag SP Primers.

Loaded 15 rounds with 180 grain HPs, H110 17 to 21 grains with CCI SR Mag Primers.

Crimp, OAL everything the same except the primers.

Shoot them all and found:

1. The Pistol and Rifle Primers look identical, same dent, no smearing/flowing, no signs of over pressure.

2.  Notice on the lighter loads, 17 to 19 grains of H110, that the Mag Rifle Primer rounds had a bit more recoil than the pistol primer loads.       Didn't notice any difference in recoil in the heavier loads.

3. All brass extracted easily and nothing to note as a problem regarding brass deforming.

4. NO FTFs, now have 150 rounds thought this gun, 38s, 357 mag, 357 max and not 1 single FTE.  Very Happy.

5.  Old guy can't see, ordering a scope base, mounts and a scope.  New Williams iron sights to be in classifieds shortly.

BB

[quickdtoo]

I suspect #5 is the reason there are no target pics or accuracy reports!!   A peep sight would be an alternative, my old eye can still shoot good with em, thanks for the report.  

Tim

[bikerbeans]

Quick,

Tried the peep, astigmatism gave me an oblong peep.  Couldn't figure out which side of the oblong to lineup the fire sight.  My peep sight is now Oldsoldja's problem. 

I was more concerned with the integrity of the small pistol primers than accuracy, but my first groups with the lighter loads (17 to 18 grains)were better, about 1.5" @ 50 yards.  My eyes get tired pretty quickly using iron sights so after about a dozen rounds all bets are off with open sights. 

I figure if I tell folks I am shooting way over MOA i probably don't need to post a pic to get them to believe me.

BB

[quickdtoo]

 

[bikerbeans]

One thing I almost forgot regarding the 357 Max, it is possible to size and load 357 Max brass in a Dillon SDB press with the Dillion 357 Mag/38Spc dies.  It however ain't easy and as it turns this progress press into a single stager.  Also requires a couple of other tricks and I don't reccommend doing it.  Some folks are so cheap they will not spend $25 bucks for a set of 7/8" by 14 dies.

BB