Changing from srp to lrp

[Rsadams]

How much difference in a load worked up using SRP then switching to LRP..???
I worked up my beginning load for my new 6.5 CM using federal SRP because I have plenty of SRP.... I ordered brass from starline and it is of course LRP any major changes to watch out for..????
I understand there will be a difference in case capacity and plan on backing down .3 tenths to start with then going back to my worked up load and retesting it again.... Sucks to have to do it this way but I can find SRP but LRP have been gone awhile and although I have a few thousand I was trying to conserve them because I don't shoot a lot of LRP... I have switched back in fourth in pistol loads with no problem but I thought I would ask for rifle...

Thanks for your advice in advance....
Shawn

 

[FeMan]

I have shot SRP and LRP 6.5 CM brass from the same manufacturer side by side and could not detect any difference with pressure, velocity of target. There are so many variables (especially in primers and powder), I would say results may vary and you should test. I would also look at the difference in case capacity between the two brands. That may affect things more than the primer change.

 

[Straightshooter1]

How much difference in a load worked up using SRP then switching to LRP..???
I worked up my beginning load for my new 6.5 CM using federal SRP because I have plenty of SRP.... I ordered brass from starline and it is of course LRP any major changes to watch out for..????
I understand there will be a difference in case capacity and plan on backing down .3 tenths to start with then going back to my worked up load and retesting it again.... Sucks to have to do it this way but I can find SRP but LRP have been gone awhile and although I have a few thousand I was trying to conserve them because I don't shoot a lot of LRP... I have switched back in fourth in pistol loads with no problem but I thought I would ask for rifle...

Thanks for your advice in advance....
Shawn

I've used the same load in my .308 using SRP's and LRP's and found no noticeable difference in velocities or accuracy, and that is with several different powders. But, I did find I get lower SD's and ES's with SPR's. Otherwise, the only time I've seen a difference in velocities and not as good SD's is with magnum LRP's.

 

[Kracken McGraw]

How much difference in a load worked up using SRP then switching to LRP..???
I worked up my beginning load for my new 6.5 CM using federal SRP because I have plenty of SRP.... I ordered brass from starline and it is of course LRP any major changes to watch out for..????
I understand there will be a difference in case capacity and plan on backing down .3 tenths to start with then going back to my worked up load and retesting it again.... Sucks to have to do it this way but I can find SRP but LRP have been gone awhile and although I have a few thousand I was trying to conserve them because I don't shoot a lot of LRP... I have switched back in fourth in pistol loads with no problem but I thought I would ask for rifle...

Thanks for your advice in advance....
Shawn

Starline does make SRP too.

 

[Bill Norris]

I swap from LRP to SRP and reverse using the same load in my 260AI however I did test the powder charges the first time.

 

[Rsadams]

Thank you all.... I will load up a few and go pop them off...

 

[Lone Hunter]

Same as above for me with 6XC using Peterson SRP and LRP Brass. I couldn’t tell a difference between the two on my loads. To be safe I would start lower and come back up. That is what I did as you never can tell which variable might get you.

 

[mgunderson]

Most people will find about 0.5 grain difference between srp and lrp. Srp will typically take about 0.5 grain more to make the same velocity in a 308 case for a bolt gun Be safe and back off enough.

 

[kiwijohn]

Most people will find about 0.5 grain difference between srp and lrp. SrpThis will typically take about 0.5 grain more to make the same velocity in a 308 case for a bolt gun Be safe and back off enough.

This ^^^^

 

[muleystalker]

Bottom line and more important is that you are changing brands of brass, so you should at least do a pressure test before anything else.

 

[Rsadams]

Real good advice , thank you... Just to be safe I was planning on backing down a half grain for testing because this is new starline brass and I would guess has less volume than my previous fired SRP federal brass... To me you just can't take chances.... Won't hurt anything but a few loads burned up testing.... Then I will know exactly what that new brass has in-store... Plus I have to work up a 129gr load and then will be done...

 

[Rsadams]

Just fyi the new Tikka is shooting like this with no tuning of the load yet just speed testing... Seriously one of the best shooting out of the box rifles I have ever owned... So far it's shocked me every time I have taken it out.... It's a light weight hunting rifle so I only shoot three shot groups... Center to center in the .3s measured with mitutoyo calipers , next picture is two in the same hole after that I was done it just doesn't get better than that... Unfortunately scope is a side focus 4x16 vortex and since it's more of a hunting scope the cross hairs are a little fat... But as long as the deers bigger than a half inch I am good...lol