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TJUrban
08-21-06, 09:14
Working out 223 handloads for my NRA highpower competition AR15 service rifle (ie 20" barrel, flattop receiver with detachable carry handle, regular handguards, free float tube, service rifle front sight, etc).

Want to mount a 9 or 10x scope with roughly a 40mm'ish objective lens (1" tube).

Anybody care to conjecture as to whether medium height rings are the correct answer?

Thanks in advance for any thoughts you may have on this,

Tim

C4IGrant
08-21-06, 09:20
Working out 223 handloads for my NRA highpower competition AR15 service rifle (ie 20" barrel, flattop receiver with detachable carry handle, regular handguards, free float tube, service rifle front sight, etc).

Want to mount a 9 or 10x scope with roughly a 40mm'ish objective lens (1" tube).

Anybody care to conjecture as to whether medium height rings are the correct answer?

Thanks in advance for any thoughts you may have on this,

Tim


Tim,

Save yourself a lot of hassle and just get a LT SPR mount with 1" rings.


C4

Nitrox
08-21-06, 11:04
Technically most medium rings will work with a 40mm objective. However, the scope may be too low. Standard iron sights are about 1.5" above the bore so if you are comfortable with the scope lower than the standard sights then go lower than high rings.


Also, there is not enough rail to move the scope far enough forward for a proper eye relief on most scopes. The exception is the Leupold MR/T line (still a bit too long) and ACOGs.

The solution to the eye relief problem is either suck it up, use and ARMS or GG&G rail extension, or use a LaRue SPR mount. I used the SPR mount because by the time you buy the rings and rail adapter it costs more and is more complex.

To give you an idea of the proper height and length here is my AR with an SPR mount and 3.5X10X40mm Leupold. The height is very close to the height of standard irons. The scope in the pictures is not set correctly, and could use being mounted further forward on the rail.

http://i6.tinypic.com/1z19oih.jpg

TJUrban
08-21-06, 13:00
Thanks very much for the prompt and helpful replies

regards,

Tim

LukeMacGillie
08-21-06, 18:17
Im using ARMS 22M's on my SPR, and they dont work, too low to allow mounting of a BUIS, They were fine on an M1A. Anyway go with the Larue, I will just as soon as I scrape up some funds.