Kyselin kys. patruunan käytöstä joskus ja vastauksena sain:
Dear Sir.
Thank you that you are interested in our cartridges. Our cartridge SB 33245 with the bullet SB 2909 is the cartridge 7,62 x 54 R.
That is the caliber of Russian origin. The cartridge with the bullet diameter .3082" is other caliber - 7,62 x 53 R of the Finish origin.
This both calibers differ not only with the diameter of bullet, but also with other dimensions:
7,62 x 54 R 7,62 x 53 R
mm mm
L1 - distance between case head and diameter P2 39,70 39,62
L2 - distance betwen case head and diameter H1 44,30 44,05
L3 - total length of the case 53,72 53,50
R1 - diameter of the case rim 14,48 14,40
P1 - diameter of the case at the case rim 12,37 12,42
alfa - angle of the jubction cone 38°01´38" 36°47'42"
S - length of the peak of junction cone 57,04 56,46
r2 - radius of junction between junction cone and coller 0,50 3,00
H1 - diameter of the collar at distance L2 8,53 8,55
H2 - diameter of case mouth at distance L3 8,53 8,50
G1 - diameter of the bullet at the case mouth 7,92 7,85
The Finish military rifles are old military Russian rifles with bores shooted out. Therefore were for the old Russian military rifles produced in
Finnland new barrels with mildly changed dimensions. Today are both calibers in C.I.P. standardized separately.
The maximal average pressures of both calibers are the same - 380 megapascal = 3800 bar, but in spite of this fact, I don't you recommend shoot our
cartridges 7,62 x 54 R from the barrel in caliber 7,62 x 53 R.
Sincerely your
Hykel
Sellier & Bellot
