18" barreled M1A

[Cecil]

Has anyone ever checked the auto ranging capability of the ART II scope with a 18" barreled M1A. Will there be a difference out to 900 yards with the shorter barrel?

[Johnny in Texas]

Has to be some.

[Cecil]

You know Johnny I thought the same thing...I guess I will find out for myself when I put the rig together.

[emmagee1917]

Just get your best guess on your MV compared to GI and plug them into a balistic program online to see the difference.
Chris

[Johnny in Texas]

You loose 20-25 fps per inch or barrel under 22"
So you loose 80-100 fps
Cecil if you shoot the hotter M118LR at 2650 fps it should make up for the difference the ART II is set up for 173 gr at 2550 fps

[Cecil]

Thanks Johnny, I"ll let you know how it went. I won't get the rifle until week after next because my FFL will be out of town next week.

[Cecil]

Yikes, I get the rifle, now I have order a stripper clip for my ART II....one of these days I'll get the scope and rifle at the range at the same time attached to one another.

[m1ashot]

You could shoot hot 170 lapuas. But you'll loose more with ammo that has a high standard deviation. 70 fps at 900 makes a difference. 4 or 5 inches or more. A lot to know at this range. My FA Tanker did not loose much with HXP. I lapped the bbl should be faster