Primer question LP for LR??

[Jeffery8mm]

In the current state of primer availability I find myself fairly well set on most primers. But I do have an abundance of LP primers such as CCI 300& 350, with emphasis on the 350. My question is...
I load for my daughters .308 a load of 150gr Lee FP GC boolit over 12gr Unique with a CCI 200. If The need ever arrises, [at the rate she likes to shoot, this could be soon!!] can I load this with the CCI 300 or 350 LP primer with no ill effects??

Might not want to use a LP for a LR in a full house cast load, but I figure for these light loads it may work??
Thanks
Jeff

[Rocky Raab]

Your reasoning is sound. It would be dicey with full-power rounds, but would probably work fine with that light load.

One thing to watch for will be misfires due to light strikes. LP primers are a bit shorter than LR and will sit deeper when fully seated. If firing pin travel is on the short side, you might get dented primers with no ignition.

I use CCI 350s (of which I have too many) in my 30-30 with a similar load, and see no differences in velocity versus using LR primers - but I do get the occasional "click."

[45 2.1]

There are some presses and primer seating dies that allow you to set the primer depth uniformly. Useing these will help in this.

[ETG]

The primary difference is the hardness of the primer - if I remember right I think the rifle primers are harder. Never noticed any difference in length among CCI but WW are short.

[Denver]

Something to watch for when using LP primers in rifles is primer piercing. I've used LP primers for years with CB loads in many different rifles with no problems except one. I have a rifle I built up with a Swede 96 action chambered for 35 Rem and it will pierce LP primers regularly where it won't do it to LR primers. I figure that the cups on the pistol primers are softer. The problem caused by piercing is that the high pressure gas will erode the firing pin and the hole in the bolt eventually.

Take care. :cbpour:

[montana_charlie]

LP primers are a bit shorter than LR and will sit deeper when fully seated. If firing pin travel is on the short side, you might get dented primers with no ignition. There are some presses and primer seating dies that allow you to set the primer depth uniformly. Useing these will help in this.
Are you referring to a seating that is of uniform depth, but not necessarily down to the bottom of the primer pocket?
CM

[45 2.1]

Are you referring to a seating that is of uniform depth, but not necessarily down to the bottom of the primer pocket?
CM

Yes.........

[AJ Peacock]

Yes.........

Wont that cause light strikes, as part of the firing pin force is dissipated in moving the primer forward in its pocket? I've seen misfires caused by not seating the correct primer all the way down into the pocket and getting the anvil solid against the bottom of the primer pocket.

AJ

[montana_charlie]

Are you referring to a seating that is of uniform depth, but not necessarily down to the bottom of the primer pocket?
CM
Yes.........
Surprising that you would advocate a method which is considered to be so detrimental to to consistent ignition...and accuracy.

Those who feel that the lower brissance of pistol primers actually enhances accuracy like to cookie-cut a paper disc into the pocket as the primer is seated. Paper ten thousandths thick is the preferred size, and (they say) it provides the support needed for consistent ignition.

But, anvil support is only one benefit of the paper disc. The other is lessened battering of the breech face by too short primers.
CM

[Eutectic]

I have had better cast bullet accuracy in the .22 Hornet and .25-20 using small pistol primers! Ball powders might be an exception.

By design, small pistol and small rifle primers have the same height however. So fit is fine. Large pistol primers are shorter in height than large rifle primers as already mentioned; so deep seating is possible. I still have used them in light loads as well however.... I seat them until the anvil just touches the bottom of the pocket... (as this is necessary for uniform ignition) This is the only primer seating I do by a depth measurement.... as other seating I like to "feel" the seat with a hand priming tool.

Eutectic

[Rocky Raab]

Ironically, this is a situation where my aversion to cleaning primer pockets might actually help. That thin layer of black ash in the pocket could be the "spacer" that allows generally good ignition with the slightly shorter LP primer.

I do take extra care to "feel" the anvil touch, using my Lee Auto Prime hand tool. It's subtle, but I can in fact feel it happen.

[beagle]

From my understanding and I haven't measured them, LP primers are just a bit shorter than LR primers. The SR and SM are supposedly the same dimensionally.

I've made this swich a lot and have encountered missfire problems in two rifles. The Number 1 Ruger in .30/06 is "iffy" and the newer M94 Winchesters with the safeties and rebounding hammers and other lawyer gimicks gave me fits until I went back to LR primer and after that, no problems.

All my Marlins handled them just fine.

I've never had any problems with the SP/SR switch.

Now, I wouldn't advise the switch with full powered J bullet loads./beagle

[Jeffery8mm]

Ironically, this is a situation where my aversion to cleaning primer pockets might actually help. That thin layer of black ash in the pocket could be the "spacer" that allows generally good ignition with the slightly shorter LP primer.

I do take extra care to "feel" the anvil touch, using my Lee Auto Prime hand tool. It's subtle, but I can in fact feel it happen.

Ditto on the cleaning the pockets. Hate it and usually let the tumbler do it.
Jeff

[Texasflyboy]

can I load this with the CCI 300 or 350 LP primer with no ill effects??

In short...yes.

Well covered ground:

CBA forum Thread using Pistol Primers in Cast Rifle Loads (http://www.castbulletassoc.org/forum/view_topic.php?id=2542&forum_id=48&highlight=Pistol+Primers)

C.E. "Ed" Harris covers this in an article or two he's written, which for the life of me I can't seem to find on the CBA forum at the moment. For the Veteran's Day shoot (2009) he was shooting cast boolit loads in his M91/30 using pistol primers and small charges of bullseye or similar fast burning pistol/shotgun powders.

He is a frequent user of Large Pistol Primers in lieu of Large Rifle when shooting cast loads.

Ed likes one powder and one primer to simplify life. Seems to work for him.

[45 2.1]

Surprising that you would advocate a method which is considered to be so detrimental to to consistent ignition...and accuracy.
Maybe you should investigate how long this has been done, which has been for quite a long time under various conditions. The CBA has extensive usuage of this substitution. Should you care to investigate, the big ammunition makers seat primers a certain distance below the case head (which usually doesn't coorespond to the bottom of the pocket).

Those who feel that the lower brissance of pistol primers actually enhances accuracy like to cookie-cut a paper disc into the pocket as the primer is seated. Paper ten thousandths thick is the preferred size, and (they say) it provides the support needed for consistent ignition. A blackpowder understanding of the situation.

But, anvil support is only one benefit of the paper disc. The other is lessened battering of the breech face by too short primers. One place this isn't to be done is higher pressure loadings. A member or two here has trashed a rifle doing so. Low pressure applications only.

I do a lot of controversial things here. I also get superb accuracy by doing them, as have others that have adopted my methods. I'm an experimenter, not a blaster. There is no substitute for trying something yourself.

[mpmarty]

Over a year ago I bought 30,000 Wolf LP primers and liked them. I then tried to buy a like amount of their LR primers and was told "so sorry charlie, sold out". What to do, what to do? Voila! I started loading all my cast boolit 7.62X51, 7.5X55, 30/284 and 45/70 rounds with the Wolf LP primers. They work great in my Marlin 1895, my Savage pillar bedded bolt gun, my converted Saiga and all three of my K31s. Accuracy is great even with my favorite 28,000 psi BLC2 loads in the 7.62 Nato. No hang fires and no pierced primers either. I figured what the heck if a 44 magnum works with LP primers at over 40,000 psi why should I worry about nearly half that?

[rob45]

There is no substitute for trying something yourself.

I agree; that statement is probably the largest consideration.

Everyone's gun is different. One gun may have a harder firing pin strike than another, even if those two guns are of same make.

Everyone's load is different. The powder being used has significant impact on its ability to ignite with a given type of primer.


This situation is no different than any other set of experiments- start conservatively and keep the variables to a minimum. Load a few samples with a powder known for easy ignition with that type of primer. If problems arise with YOUR combination of gun and load, then start looking for solutions. But you don't need a solution to a problem that may not be there in the first place.:-)

[fecmech]

Many years ago when all I had was LP primers and a Rem 788 .243 I ran about 500 rds through it using them. I loaded a 60 gr Sierra to about 3500 fps with 45 grs of H-380 and never had a problem. The gun would stay under .75"@100 yds all day long and I have a .250" 5 shot group using that load!