ADM help needed ASAP

[deadduck357]

Thanks again Trident.

[marsh1]

Marsh1, I was also looking into Bobro mounts but all I could find on their site was mounts for Aimpoints. Does Bobro have another site ?

http://www.bobroengineering.com/brow...y/opticmounts/

Also how do you like the XTR-14 ? I wanted to hold out for the SS 1-4x but who knows when that will be available.

They make the scope mounts in standard and ext. The web site is missing other mounts as well.

The XTR is nice glass for the money. Good 1X performance and the eye position is pretty forgiving.

[deadduck357]

Thanks Marsh1. Pics sure help out.

[JSantoro]

From there does the drop have anything to do with height over bore?

Given the info in this thread, here's the reticle we're talking about:

http://www.burrisoptics.com/pdf/Ball...20Reticles.pdf

That's a BDC reticle, ergo, those aimpoint stadia are valid presuming a 62gr FMJ @ 3025fps at a particular sight height. The sight height isn't specified, but suffice to say that changing ONE factor has an impact on the ballistic arc. This is reinforced by the chart at the bottom of the cited page, where they plot the differences between rounds and display holds in relation to the stadia of a given range. Alter the sight height, none of that is valid.

So, unless you're putting on your Dutch Uncle hat and want him to get something that will change the sight height and make all that lovely pre-plotted info into total horseshit so that he's forced to do more research and shooting that he would otherwise have to so that he knows the relationship with his preferred round with the stadia on the reticle....

Yeah, height over bore has an impact, and you tacking an LOL on the end in no way changes that. Have as many beers as you feel you need, you're wrong to think it's of no consequence at all. That's an entry-level ballistic plot input.

[shootist~]

I am trying to think through if that matters. You zero as per the instructions and the bullet is on target dead center in the reticle. From there does the drop have anything to do with height over bore?

Marshall

I ran comparisons for different sight heights in JBM Ballistics at my altitude of 5,000 ft and it's small enough to ignore.

I used 1.8" Vs 2.7" sight height; 1.8" being the lowest example for sight height listed in the Burris chart and 2.7" being what I use for a 30mm Larue SPR mount. Data was for a 55 gr Hornady FMJBT at 2,900fps with a 200M zero. The difference in drop at 500 meters was 1.3", or in MOA terms - about a gnat's ass.

Atmospheric conditions - such as altitude - can have a more significant effect than sight height.

[marsh1]

Given the info in this thread, here's the reticle we're talking about:

http://www.burrisoptics.com/pdf/Ball...20Reticles.pdf

That's a BDC reticle, ergo, those aimpoint stadia are valid presuming a 62gr FMJ @ 3025fps at a particular sight height. The sight height isn't specified, but suffice to say that changing ONE factor has an impact on the ballistic arc. This is reinforced by the chart at the bottom of the cited page, where they plot the differences between rounds and display holds in relation to the stadia of a given range. Alter the sight height, none of that is valid.

So, unless you're putting on your Dutch Uncle hat and want him to get something that will change the sight height and make all that lovely pre-plotted info into total horseshit so that he's forced to do more research and shooting that he would otherwise have to so that he knows the relationship with his preferred round with the stadia on the reticle....

Yeah, height over bore has an impact, and you tacking an LOL on the end in no way changes that. Have as many beers as you feel you need, you're wrong to think it's of no consequence at all. That's an entry-level ballistic plot input.

Nice of you to not include my full quote where I said "I am trying to think trough if that matters". "I will have a few beers and ponder it." but thanks for the clarification.

I will get the OP his measurement as promised tomorrow.

[Singlestack Wonder]

Go with the ADM Recon X. It gives one more flexibility than a non-extended version when moving to different rifles requiring varying amounts of eye relief.

[ALCOAR]

I ran comparisons for different sight heights in JBM Ballistics at my altitude of 5,000 ft and it's small enough to ignore.

I used 1.8" Vs 2.7" sight height; 1.8" being the lowest example for sight height listed in the Burris chart and 2.7" being what I use for a 30mm Larue SPR mount. Data was for a 55 gr Hornady FMJBT at 2,900fps with a 200M zero. The difference in drop at 500 meters was 1.3", or in MOA terms - about a gnat's ass.

Atmospheric conditions - such as altitude - can have a more significant effect than sight height.

I like your way of doing business Nice info contained in that reply...although I never believed the scope in question was an odd ball that would be different than any other scope made that would mount in an ADM/Bobro/Larue mount.

[marsh1]

The ADM Recon and Recon X are the same height over bore. They sit lower that the Burris shown in the link above. The measurement coresponding to A in the Burris chart is .89" for the ADM vs 1" for the Burris.

[deadduck357]

Marsh1, do you have a pic of the bottom(underneath) pic of the Bobro scope mount ? Trying to compare the secure points between the Bobro and ADM.