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 So if I move a scope in a mount up one picatinny section, will it change the zero significantly?
cableguy221  [Team Member]
3/1/2013 10:37:13 PM
I have a scope in a larue SPR 1.5 mount. I moved it up one notch. If I'm going to shoot a competition(with most shots being between 0-200M) with it, do I really need to rezero it? I can't imagine the zero would change much.
Crowcreek  [Member]
3/1/2013 10:47:26 PM
I'll say theoretically that the only effect it will have is putting the weight a little more forward on the barrel.

This will slow the recoil arc of the rifle and make the point of impact a little lower.

If it has much effect at all, I'll feed your cat for a day.
aardvark_ratnick  [Team Member]
3/1/2013 10:49:35 PM
yes
_Matt_  [Team Member]
3/1/2013 10:50:04 PM
Originally Posted By Crowcreek:
I'll say theoretically that the only effect it will have is putting the weight a little more forward on the barrel.

This will slow the recoil arc of the rifle and make the point of impact a little lower.

If it has much effect at all, I'll feed your cat for a day.


The bullet is long gone from the barrel before any recoil would affect the trajectory


To answer the question, it should be minute of man, but may be off, so you should shoot to verify
ar2de  [Member]
3/1/2013 10:50:40 PM
It shouldn't affect the zero, but rifles (esp light weight ones) are sensitive to changes. A couple rounds down range will tell for sure.
Flats  [Member]
3/1/2013 10:52:57 PM
Theoretically, no. The geometry hasn't changed. If I were shooting a competition I would check, though.
TXJoe  [Member]
3/1/2013 10:59:04 PM
So you basically took the scope off the rifle and re-mounted it and you think the zero won't change?
cableguy221  [Team Member]
3/1/2013 11:02:04 PM
Originally Posted By TXJoe:
So you basically took the scope off the rifle and re-mounted it and you think the zero won't change?

It doesn't change if you mount it to the same bracket it was one before. It moved up a bit further. It will change, but not significantly I would think.
ugagrad06  [Team Member]
3/1/2013 11:02:55 PM
Originally Posted By TXJoe:
So you basically took the scope off the rifle and re-mounted it and you think the zero won't change?


You must not know larue or their spr mount. Zero shift guaranteed. Many many many have tested it.

Posted Via AR15.Com Mobile
Mosspointers  [Member]
3/1/2013 11:04:15 PM
Geometrically, yes but not enough to matter at those distances.
EFB16ACRX  [Life Member]
3/1/2013 11:05:49 PM
Well, thats going to depend on who machined the upper you have. Might not move at all, might be 2 feet off ( I would hope not ).
chupacabras  [Team Member]
3/1/2013 11:06:12 PM
It moved.

TXJoe  [Member]
3/1/2013 11:06:56 PM
Originally Posted By ugagrad06:
Originally Posted By TXJoe:
So you basically took the scope off the rifle and re-mounted it and you think the zero won't change?


You must not know larue or their spr mount. Zero shift guaranteed. Many many many have tested it.

Posted Via AR15.Com Mobile


Very interesting, I did not need to know this as I am almost sure I will not be able to afford one.

BrdChris  [Member]
3/1/2013 11:09:57 PM
I had a laser alignment class at work today. Apparently your screwed.
iluvguns  [Team Member]
3/1/2013 11:13:08 PM
if your shooting a competition then i would go ahead and check your zero. That way your not wondering if your misses were from not being zeroed.

RECONSIX  [Member]
3/1/2013 11:15:27 PM
Originally Posted By TXJoe:
Originally Posted By ugagrad06:
Originally Posted By TXJoe:
So you basically took the scope off the rifle and re-mounted it and you think the zero won't change?


You must not know larue or their spr mount. Zero shift guaranteed. Many many many have tested it.

Posted Via AR15.Com Mobile


Very interesting, I did not need to know this as I am almost sure I will not be able to afford one.



They're only $210 or you could get a non-QD mount for $50 less.

Darkstar117  [Team Member]
3/1/2013 11:19:05 PM
Originally Posted By TXJoe:
Originally Posted By ugagrad06:
Originally Posted By TXJoe:
So you basically took the scope off the rifle and re-mounted it and you think the zero won't change?


You must not know larue or their spr mount. Zero shift guaranteed. Many many many have tested it.

Posted Via AR15.Com Mobile


Very interesting, I did not need to know this as I am almost sure I will not be able to afford one.



http://www.laruetactical.com/larue-tactical-spr-s-mount-lt-158
Keith_J  [Life Member]
3/1/2013 11:23:02 PM

Originally Posted By _Matt_:
Originally Posted By Crowcreek:
I'll say theoretically that the only effect it will have is putting the weight a little more forward on the barrel.

This will slow the recoil arc of the rifle and make the point of impact a little lower.

If it has much effect at all, I'll feed your cat for a day.


The bullet is long gone from the barrel before any recoil would affect the trajectory


To answer the question, it should be minute of man, but may be off, so you should shoot to verify

You think. But there is a reason the Ransom Rest for pistols recoils. But the AR15 platform is a straight recoil design. You still can get a point of impact change with different positions.