Primers LP vs LR
- Thread starter shuz
- Start date
I've never bothered to figure that out, because large rifle primers are "taller" than large pistol primers.
There's a chart floating around somewhere, which lists the dimensions of each type. SMALL rifle primers and SMALL pistol primers have the same dimensions and I have done quite a bit of substituting in the 357 Mag rifle/revolver for logistical considerations. Note that not all cast bullet rifle loads are necessarily "low pressure" either. I typically stick with RIFLE primers in RIFLE brass, but have used rifle primers in pistol brass also.
EDIT:
Holy cow! There's a bunch of 'em out there. You pick which one(s) you want to trust:
duckduckgo.com
There's a chart floating around somewhere, which lists the dimensions of each type. SMALL rifle primers and SMALL pistol primers have the same dimensions and I have done quite a bit of substituting in the 357 Mag rifle/revolver for logistical considerations. Note that not all cast bullet rifle loads are necessarily "low pressure" either. I typically stick with RIFLE primers in RIFLE brass, but have used rifle primers in pistol brass also.
EDIT:
Holy cow! There's a bunch of 'em out there. You pick which one(s) you want to trust:
smal large rifle pistol primer dimension chart at DuckDuckGo
DuckDuckGo. Privacy, Simplified.
Last edited:
The reason for the question is that my group size at 100 yards nearly doubled in size when I substituted CCI 300 large pistol for the Winchester western large rifle i had been using. The load is a mild cast boolit load of 14.3g of Reloder 7 and a 100g Saeco boolit in a .250 Savage mdl 16 bolt gun.
JonB
Halcyon member
My 2¢ here,
Please don't take offense,
But did you give them enough of a test? Did you try this more than one visit to the range?
Sometimes, I have a bad day at the range...you know large groups.
Next time I go to the range, and groups go back to what I expect with a given gun and batch of ammo.
Could be stress/heartrate, sun/eye strain, or maybe Caffeine?
I have found my old eyes have more issues on sunny days, even though my range is usually shaded.
Just driving the 5 miles through open farmland on a sunny day, to get to the range, can stress my eyes for a period of time.
Please don't take offense,
But did you give them enough of a test? Did you try this more than one visit to the range?
Sometimes, I have a bad day at the range...you know large groups.
Next time I go to the range, and groups go back to what I expect with a given gun and batch of ammo.
Could be stress/heartrate, sun/eye strain, or maybe Caffeine?
I have found my old eyes have more issues on sunny days, even though my range is usually shaded.
Just driving the 5 miles through open farmland on a sunny day, to get to the range, can stress my eyes for a period of time.
Snakeoil
Well-Known Member
We have at least one member who does very well in our matches that has been using LPP in his .32-40 and .30-06. If I run out of LRP before the become available again, I'll be using LPP. Might have to tweak my load. We'll see.
You just do not want to use them in HP loads. There is a risk of rupture according to the experts.
You just do not want to use them in HP loads. There is a risk of rupture according to the experts.
Just a guess, but seating the shorter pistol primer in the deeper rifle primer pocket MAY be an issue with consistent ignition. This may not be true in all guns or for every cartridge, but you may be, in effect, losing some firing pin protrusion, or using up some momentum seating the shorter primer with the firing pin - or both.
Between my eyes and my patience (either of which is subject to come up short these days), I find that more and more it's ME, when there's something "not quite right" at the target.
Good point. I can do what shuz did - with the same gun and load on two different days.
Matt
Active Member
My experience has been that using pistol powders in rifle cases is that pistol primers work fine. Watch that fine powders like Red Dot, Bullseye. 231 etc don’t migrate into the flash hole, I’ve seen a direct correlation of vertical stringing if I don’t lightly tap them nose down
before firing. With rifle cases and rifle powder in light cast loads (primarily 4198 and 4759 ) I’ve had less accuracy with the loads I’ve tested with pistol primers. I’ve never loaded anything with RL7 so I don’t know where it falls in this.
before firing. With rifle cases and rifle powder in light cast loads (primarily 4198 and 4759 ) I’ve had less accuracy with the loads I’ve tested with pistol primers. I’ve never loaded anything with RL7 so I don’t know where it falls in this.
Ian
Notorious member
Reloder 7 needs more poop than a CCI 300 can produce in order to yield consistency. I doubt your 16 has issues setting them off unless you aren't crushing the pellet correctly when seating them.
Where I see improvement by switching to CCI (sometimes) is when using a powder like Titegroup at very low loading density. If you have any WLP primers you can try those, they have a lot of brisance for what they are and generally provide about equal results for me as LRP in reduced loads.
Where I see improvement by switching to CCI (sometimes) is when using a powder like Titegroup at very low loading density. If you have any WLP primers you can try those, they have a lot of brisance for what they are and generally provide about equal results for me as LRP in reduced loads.
Ian--All 30 rounds that I loaded with 14.3g of Reloder 7 and the 100g Saeco went "bang". What is the basis for your statement that Reloder 7 needs more poop than a CCI 300 gives? Do you have information that CCI 300's "have less poop" than CCI 200's?
The reason I am going through this issue is that I have 15000 or so of Large pistol primers of either CCI 300, Rem 2-1/2's or WW WLP's and only about 4000 CCI 200' or Rem 9-1/2's. These days I find myself shooting much more cast boolit rifle loads than handgun loads.
The reason I am going through this issue is that I have 15000 or so of Large pistol primers of either CCI 300, Rem 2-1/2's or WW WLP's and only about 4000 CCI 200' or Rem 9-1/2's. These days I find myself shooting much more cast boolit rifle loads than handgun loads.
Ian
Notorious member
Call Olin and ask them if all you are interested in is primer information. If you want to know what happened to your groups when you switched, I told you. How do I know? Experience, lots and lots of it. RX-7 is a triple-based, high-nitro powder and is very unique. It is heavily deterred yet once lit burns very consistently at low pressure. The key is "once lit". There is a big difference between going bang and going bang with efficiency. Your target at I are both trying to get you to understand that. If you're set on using the CCI-300s, drop down to Unique and rework your load. If you insist on RX-7/CCI-300, the only thing I can think of that might help is Dacron, but RX-7 and Dacron don't always play well together, particularly in bottlenecked cases.
fiver
Well-Known Member
try the winchesters.
i will say that swapping out winchester LR primers down to their LP primers meant i had to increase my 30-06's 2400 load UP almost a full grain to get my sight settings back.
you might just be suffering from a system change with the primer swap, it may not be bumping the bullet forward like the rifle primer does so your 'timing' is off.
i will say that swapping out winchester LR primers down to their LP primers meant i had to increase my 30-06's 2400 load UP almost a full grain to get my sight settings back.
you might just be suffering from a system change with the primer swap, it may not be bumping the bullet forward like the rifle primer does so your 'timing' is off.
CWLONGSHOT
Well-Known Member
100% there is a difference!
The bigger question is how much difference it makes.
The biggest difference is height. Large pistol isnt as tall as large rifle. But they are both .210 in diameter.
The difference can be compound, amount of compound and cup thickness.
Good call to contact manufacturer for there exacts. Or as much as they will share with ya.
I had a chart that I cannot find showing cup thicknesses. I also remember speaking with CCI tech who confirmed SR was same as SPM. At least at that time twenty years ago.
CW
The bigger question is how much difference it makes.
The biggest difference is height. Large pistol isnt as tall as large rifle. But they are both .210 in diameter.
The difference can be compound, amount of compound and cup thickness.
Good call to contact manufacturer for there exacts. Or as much as they will share with ya.
I had a chart that I cannot find showing cup thicknesses. I also remember speaking with CCI tech who confirmed SR was same as SPM. At least at that time twenty years ago.
CW
I use some LPP in some light 30-30 loads, and used quite a lot of them in various rimmed cartridges when I shot blackpowder catridge silhouette.
As for substituting CCI 300s for WLR, the WLR are/were reputedly the hottest of the LR primers. Maybe a magnum LPP would do better, thinking that they might have more brisance along with a thicker cup.
As for substituting CCI 300s for WLR, the WLR are/were reputedly the hottest of the LR primers. Maybe a magnum LPP would do better, thinking that they might have more brisance along with a thicker cup.
Bret4207
At the casting bench in the sky. RIP Bret.
If there is that much of a difference and the only thing you changed is the primer, then it's got to be that there is enough difference in primers with R7 to make the difference. You could trysome of the tricks for harder to ignite powders, like a firmer crimp to build pressure, but another powder might be a more effective answer.
I've used lots of PP in place of RP, sometimes it makes a difference, other times it doesn't.
Ian
Notorious member
WLP.
RBHarter
West Central AR
In a pistol load , H110 in a 45 Colts, I switched to a Mag from LPP CCI and cured the problems with the load , and I didn't like it at 265 gr 1240 fps .....
I switched from WLR to CCI 300 and cut groups in an SKS from 8" at 75 yd to 3×5" at 100 with just the primer change . 200 gr PP and 23gr of IMR 4350 .
Really if I'm not shooting CCI it's because I'm cleaning up scraps .
I haven't done any serious side by side other than above to see how much it matters . I do know that it makes a difference to "tip up" 45-70-405s with 10-12 gr of Unique I doubt that PP vs RP would make a big difference there .
I did load some 32 Rem with 4350 and LMP there didn't seem to be a big difference in a Model 14 Rem . I still don't have the feel for a slide action rifle though . There's a lot of wiggle room for operator error there .
I switched from WLR to CCI 300 and cut groups in an SKS from 8" at 75 yd to 3×5" at 100 with just the primer change . 200 gr PP and 23gr of IMR 4350 .
Really if I'm not shooting CCI it's because I'm cleaning up scraps .
I haven't done any serious side by side other than above to see how much it matters . I do know that it makes a difference to "tip up" 45-70-405s with 10-12 gr of Unique I doubt that PP vs RP would make a big difference there .
I did load some 32 Rem with 4350 and LMP there didn't seem to be a big difference in a Model 14 Rem . I still don't have the feel for a slide action rifle though . There's a lot of wiggle room for operator error there .