ORIGINAL: elmer deer
I have a few questions for you guys to answer,
1) Does seating the bullet .005 off the lands change velocity as opposed to seating .020 off the lands?
2)Does a light crimp make velocity slower as oppossed to no crimp?
3)I shot some reloads with my 7mm rem the other day, it was -15c or a 5f (cold) my loads were
RL22 66.5gr with 140 accubonds out of a 26" barrel,Sauer 202, my average speed with these loads was 2975fps.The Nosler book list that laod at 3240fps with a 24' tube, WHY THE BIG DIFFERENCE does the cold affect the velocity that much or is my barrel a bit slow? It is a new gun this was the 2nd time at the range with it.
Sorry for all the questions guys
Thanks
Elmer
Yes seating depth has a direct relationship to pressure and velocity. Its a give and take. Closer to the lands you seat, the more pressure spike you can have, but now you opened the area in the case for explosion, but further from the landsyou give the bullet more of a running go but less space in the case. I have made loads that hit the lands, and I hit pressure signs early. I moved them back some and was able to go up a grain or even two.
A light crimp probably will make pressures go up some.
I think Nosler was way off on that load. I got a good friend I shoot with that posts on here, that also uses that load, and his shoots 3050fps consistently. I dont believe much has to do with the cold, but mroe that nosler is far off with this load.