Rifle Scopes Hello everyone! New with a question about my Nikon M-223

[hyrulejedi86]

Hey guys, I'm new on this forum from Ohio! I just recently built myself a standard 16" AR-15 in 5.56 and have since aquired a Nikon M-223 2-8 x 32 with Nikoplex rapid action turret. So far the scope is awesome, I love the feel, the clarity and the crosshairs are sharp. My question is more about using the rapid action turrent, as I have a 16" AR15 I know that my velocity with a 3240fps round will probably be closer to 3000 fps or even 2900fps. How is this, once the scope is zeroed at 100 yards, going to affect my POI using the pre marked distances on the turret? How can I compensate for that? I am aware of the SpotOn program but it isn't going to work as well without the BDC. Ontop of that I don't have a Chrono to figure out what the velocity is, at least not yet. I'm thinking about getting one because I have been reloading now for about 6 months. I have done 9mm exclusively and am moving onto 223 so I have a feeling that my handloads will end up being even slower than the factory 3240 loads, but hopefully not by much.

I'd appreciate any feedback as well!

 

[hk dave]

Sorry, want to help, but I can't figure out what the question is.

I can say a few things that will help... first off, all different ammo will have a different POI. You are correct in that your 16" barrel will probably not produce 3240fps.

You compensate by turning the turret to match the amount of difference between your aiming point and your POI.

If this does not make sense to you, I highly suggest you read up on how riflescopes work, what bullet trajectory means... and perhaps take a beginners class in precision marksmanship.

 

[hyrulejedi86]

I suppose i should clarify my question a little, sorry! What I ment was the turret on that scope is calibrated for 100 yards 200 yards 300 yards etc but that relies on a specific bullet weight and velocity. It's essentially a custom turret. My velocity is a good bit less than 3240 so how much difference can i expect once zeroed when using that turret?

Sent from my DROID RAZR

 

[Temp9]

Check it out for yourself. Google JBM Ballistics and use their calculator to figure out what the drop at 3240fps and your velocity is, then compare.

 

[Name Enough]

I would say go and shoot it and see what the difference is. I use four Zeiss scopes on four rifles with a Z600 reticle that performs differently for each rifle. Just because the reticle or turret say 200 or 300 yards doesn't mean you are stuck with that. On my Nikon my 200 is 200 plus 4 clicks with my hand load 60 grain Nosler soft points. This info is recorded for quick reference since I have 6 AR pattern rifles.
If you are going to reload if pays to get a Chromo. I would almost say you are wasting your time reloading if you don't chromo your results.
Make sure you record your results for future reference. The max loads don't always give you the best accuracy.

 

[hyrulejedi86]

Fair enough,a chrono is on my list thigh very soon.

Sent from my DROID RAZR

 

[Joe L]

I have a 2-8x M-223 with the BDC reticle. I am pretty sure you can use the Spot-on program to calculate what the distance represents for your muzzle velocity just like you can re-calculate what the marks on the BDC reticle represent. I have used the Spot-On program to calculate the scale when using the scope on my .308 bolt gun, for example.

Get the Spot-On app and play with it a little and I bet you can figure it out. The 100 yard turret mark will become a 94 yard mark, for example. And the 200 yard may really be accurate at 175 or so.

Joe

 

[bman940]

Hy, Good question and one I have answered many times. I have a DPMS Sweet 16 that I chronographed 55 gr. Win. BST rated at 3240 fps. My result was around 3120 fps at 10 feet from the barrel. I next went to Spot On and checked the trajectory using the Custom Loads section to see what the difference in drop would be. I have shot my Sweet 16 with a M-223 3-12 Rapid Action Turret to 600 yards on multiple occasion's hitting a 10 inch plate. My DPMS 24 inch barrel also pinged steel at that distance and Chronographed only 70 fps faster at 3190 fps. So, from your question above, I think you will be just fine without having to worry about any hold over at all. Just dial your distance and put the crosshairs on the target.

http://i1216.photobucket.com/albums/dd363/bman940/M-223 3-12/M-2233-12dpms.jpg

 

[hk dave]

Hmm by the OPs question and his subsequent response... I think there must be a misunderstanding.

OP, i mean no disrespect by this question, just trying to help... do you know the term "Zeroing a scope"?

 

[sawman556]

You need dope for each load. If you are reloading a chrony is a must have, IMO. I wouldn't use a marked turret unless it is a custom dial for my exact load. As far as AR-15's go I don't find much difference in military loads inside 300yds. My dope for M855 works pretty well for XM193.