SRP vs LRP with the Creedmoor's

[Mike in Oregon]

I'm getting ready to buy new 22 and 6 CM brass and I'm unable to find a thread I read on this matter. I plan to shoot a 62-grain in the 22CM and an 80-grain in the 6CM both ELD-VT's. Both will be used for long-range rock chuck and PD's. So why the two different primer sizes?

 

[Bill Norris]

I'm getting ready to buy new 22 and 6 CM brass and I'm unable to find a thread I read on this matter. I plan to shoot a 62-grain in the 22CM and an 80-grain in the 6CM both ELD-VT's. Both will be used for long-range rock chuck and PD's. So why the two different primer sizes?

The SRP is believed to produce better ignition than the LRP especially in the larger cases with ball powders. But for using ball powders the LRP will probably be the way to go.

 

[Kracken McGraw]

Primer pockets should last longer too on the small primer type due to more case head brass holding everything together.

 

[Mike in Oregon]

Never shooting these rifles yet and just starting to get components for load development, sounds like I do a hail Mary and hope I get it right the first time with the brass.

 

[Kracken McGraw]

With the srp brass you also run into getting the 700 actions bolts bushed or getting customs with a .062 firing pin.

 

[Mike in Oregon]

With the srp brass you also run into getting the 700 actions bolts bushed or getting customs with a .062 firing pin.

The 22CM is a Custom No. 1 and the 6CM is a Custom Howa.

 

[Mike in Oregon]

Leaning to the LRP's...

 

[jxb]

Someone said the LRP's do better in the cold, no idea if that's true or what they consider cold. I've had no issues with SRP to about 20F but I wouldn't call that cold.

 

[Mike in Oregon]

What research I have done is saying for the 22 CM SRP's makes more sense to me. But the 6CM, it sounds as if the LRP's are the way to go.

Cold weather does not come into play, and the firing pin will not be an issue either.

 

[ronsatspokane]

How hot are you going to load? SRP primer pockets will last longer if you are loading on the hot side. I run CCI 450's in them. Small rifle magnum primers that is. Got the best results with those in F Class level loads (as in loads on the warm side).

 

[Mike in Oregon]

How hot are you going to load? SRP primer pockets will last longer if you are loading on the hot side. I run CCI 450's in them. Small rifle magnum primers that is. Got the best results with those in F Class level loads (as in loads on the warm side).

Always chasing fps, so at the top end sir.

 

[Gary in MD]

I'm going through the same process, getting brass together for a 22CM.
I bought the Alpha sr primed brass, but I've read enough on the www to see that some guys are having ignition problems using the sr primers. So now that's in my head, I just ordered a hundred with the lg primer pockets.
Decisions decisions....

 

[Fuj]

Medium rifle cases puts you at a tipping point. Varget and faster
powders you could use SRPs. But when powders like H-4350 and
slower, and ball poders, it's LRP's for me......

 

[Nevned]

I'm getting ready to buy new 22 and 6 CM brass and I'm unable to find a thread I read on this matter. I plan to shoot a 62-grain in the 22CM and an 80-grain in the 6CM both ELD-VT's. Both will be used for long-range rock chuck and PD's. So why the two different primer sizes?

I use 450's, 205M's and 7/12s SRP in Lapua 6GT and 6CM cases exclusively with H4350 and still have tight primer pockets after 10-12 loadings. I live in the desert SW and cold temperatures are not an issue for ignition....thankfully

 

[nmkid]

LRP and forget about primers!

 

[Rob01]

Have used LRP in my 6.5 Creed since 2008 and never an issue and excellent accuracy. Used LRP in my 6Creed since 2013 and never a problem and excellent accuracy. I see no reason to go SRP.

 

[STS]

This question comes up frequently on here. I've posted this before, but this seems like a good opportunity to pass along the info again. I live in Southwest Montana, and it can get a little on the cool side around here. That being said, I am able to test the 'cold weather/small primer' thing quite easily. It was -38F here one morning three years ago. I decided that I would probably never get a better chance to test cold weather primer performance than that day. By the time I got things gathered up and to the range it had warmed up to a tropical -22F.
The rifle was a R700 .22 CM with Lapua brass, VV N-160 and CCI 450's. I sat the rifle, ammo and chronograph on the bench and retreated to the heater in the pickup with the chrono battery. It all sat out there for 30 minutes in the cold. I shot 10 rounds which all went bang, had a SD of less than 10 and were about 50fps slower than they normally ran. There were no delays or outright hangfires. In other words, nothing out of the ordinary other than the velocity. It's not uncommon for it to be below zero when we're out calling coyotes so things need to be right.
I make sure the ignition of the action is not compromised and has a fresh 24# spring, something right around .250 of firing pin fall and no garbage or lube in the bolt. And NO LIGHT WEIGHT FIRING PIN. In addition, make damn sure the primers are seated with the anvil in contact with the bottom of the primer pocket. Excluding those folks who try to use ball powder, I contend that if you are having ignition issues with small rifle primer .22 or 6 CM loads. there's probably something that needs some attention in the action.
There are small rifle primers and then there are small rifle primers. They are not all created equally. I would strongly recommend that Federal 205's be avoided in the larger cases. I had a .22x47 Lapua that did hang fire with a Federal 205M at -18F one morning coyote calling. The 205 is the lowest brisance primer of the commonly used SR primers and will not get the job done in COLD weather. Stay with the CCI 450 or Rem 7.5 and you won't have any trouble if your action is working properly and your using stick powder.

 

[Frankm]

….. and one thing not mentioned as a side issue; srp s have been much more readily available last 3-4 years along with better pricing …. Food for thought should the performance aspects meet your criteria on srp.

 

[Gary in MD]

This question comes up frequently on here. I've posted this before, but this seems like a good opportunity to pass along the info again. I live in Southwest Montana, and it can get a little on the cool side around here. That being said, I am able to test the 'cold weather/small primer' thing quite easily. It was -38F here one morning three years ago. I decided that I would probably never get a better chance to test cold weather primer performance that that day. By the time I got things gathered up and to the range it had warmed up to a tropical -22F.
The rifle was a R700 .22 CM with Lapua brass, VV N-160 and CCI 450's. I sat the rifle, ammo and chronograph on the bench and retreated to the heater in the pickup with the chrono battery. It all sat out there for 30 minutes in the cold. I shot 10 rounds which all went bang, had a SD of less than 10 and were about 50fps slower than they normally ran. There were no delays or outright hangfires. In other words, nothing out of the ordinary other than the velocity. It's not uncommon for it to be below zero when we're out calling coyotes so things need to be right.
I make sure the ignition of the action is not compromised and has a fresh 24# spring, something right around .250 of firing pin fall and no garbage or lube in the bolt. And NO LIGHT WEIGHT FIRING PIN. In addition, make damn sure the primers are seated with the anvil in contact with the bottom of the primer pocket. Excluding those folks who try to use ball powder, I contend that if you are having ignition issues with small rifle primer .22 or 6 CM loads. there's probably something that needs some attention in the action.
There are small rifle primers and then there are small rifle primers. They are not all created equally. I would strongly recommend that Federal 205's be avoided if the larger cases. I had a .22x47 Lapua that did hang fire with a Federal 205M at -18F one morning coyote calling. The 205 is the lowest brisance primer of the commonly used SR primers and will not get the job done in COLD weather. Stay with the CCI 450 or Rem 7.5 and you won't have any trouble if your action is working properly and your using stick powder.

That’s great info, thanks for posting

 

[charlie b]

I've used the Fed AR match primers in my 6.5CM SRP Peterson brass and get very consistent results. I'm using N540 in most loads. I've also used Rem 7 1/2 and CCI 450.