Elevation issues with my 45-90

[Johnny bravo]

Good day all:grin:
Could you please enlighten me as to why my 45-90 loaded with 90gr of Swiss 4 needs 9-10mins more elevation at 300yds than my 45-70 loaded with 70gr of Swiss 3? Seems quite counter productive, what with the BP prices and all!?

Forgot to mention, the 45-90 is shooting 540gr PP bullets patched to bore dia whereas the 45-70 shoots groove diameter 535gr Postel GG bullets.

Would be grateful for your kind input.

Regards,
JB

[semtav]

You don't say what length the barrels are..
My Win 1885 45-90 w/ 34" barrel was taking way more elevation than my 40-65 with 30" barrel til I got out to about 450 yds, then they started coming back together and are the same setting at 650. (1.05)

(90 gr Goex FFG or 85 gr Swiss 1 1/2 535 gr bullet)
(57 gr Goex FFG 410 gr bullet)


300 yds #54 - 45-90
300 yds #45 40-65


What are your 100 yd settings? may just be different configurations unless you have identical guns and sights/barrels

[Johnny bravo]

Thanks Semtav:-D
the 45-90 has a 34in bbl whereas the 45-70 has 32in.

I haven't zeroed the rifle at 100yds yet. I just used my 45-70's zero settings and JMB ballistic program to get on target. When I tried my first few shots (with the 45-70's 100yd setting) the bullets were hitting low.

My 300yd 45-70 (535gr Postel) zero = 60min
300yd 45-90 (540gr PP) zero = 70min

ATB

[Lead pot]

Barrel jump.
The faster powder gets the bullet out the barrel faster.

[semtav]

Barrel jump.
The faster powder gets the bullet out the barrel faster.


I recently acquired a 45-70 identical to my 45-90 except barrel length. will be interesting to see the differences when I get around to loading for it.