Home Forums Hunting & Shooting Ask The Gunwriters Remington 7-1/2 primers question

I checked the data I had stored in my e target and find that for 10 shot strings at 1000 yards the 7 1/2s averaged 1292 fps, SD 8.6 fps and the 450s 1290 fps, SD 12.2 fps. Statistically a tie and I would need longer strings to validate any SD comparisons. My go to loads use the 450s.

I did lookup my notes on German Salazar's testing, and with a strain gauge equipped 6XC the 7 1/2s were about 1000psi hotter than CCI BR4s. He did not test the 450s.

Thanks for the info.

Just checked some of my older testing in a .22 Hornet with Li'l Gun, and in that one 450s were hotter than BR4s--but for some reason I also didn't try any 7-1/2s..

Can't say if Star Line has done any actual comparisons, but this comes directly from the the 6 Creedmoor srp brass page:

"As with all types of cases this large with small primer pockets, it will require care in powder and primer selection in cooler temperatures to prevent hang fires. Single-based propellents are generally easier to ignite and a quality primer such as the Remington 7 1/2 BR are recommended."

I've been using 7 1/2 s with CFE223 with good results in the 6Cm, but haven't had a chance to try the load in cold weather.