Rifle Scopes Quick question/Advice regarding Spuhr & Era-tac Mounts

[dbransco]

I am picking up a S&B 5-20 Ultra Short and am contemplating either a Spuhr SP-4036 (0 MOA Cant) or ERA-TAC (20 MOA) one piece mount. I have been running Spuhr mounts and really like them and am leaning toward the Spuhr now; however, they only make a 0 MOA Cant model. This is going on a DT Covert with 26" 338 LM barrel. Unless I'm missing something, with 40MRAD of elevation travel, I believe I would be comfortable to roughly 2,000 yards having no additional cant in the mount.
Any thoughts here? Would it be more advantageous to have the cant?

thanks!

 

[Covertnoob5]

You only get 34 mils of elevation on the turret. 17 per turn. So you'll want the slanted base. Mine is also on a Covert SRS.
I thought long and hard between those 2 as well for mine.


Better to have it and not need it, than to not have it and say oh shit.....

 

[dbransco]

Thanks Covert,

thats kinda what my gut was telling me as well. Both mounts appear to be built very well.

 

[Covertnoob5]

They are. I have several era-tac mounts and they are top notch. Another thing would be to remember that because you have an SRS you'll most likey have other calibers. So that moa might be needed for other situations. And let's not forget if you decide to move that optic to an AR or something like that you might want some extra elevation.


Better to have it and not need it, than to not have it and say oh shit.....

 

[Anchor Zero Six]

Maybe I misread this but what do you mean they only make a 0 moa mount? Just bought a 30 moa spuhr.

 

[dbransco]

Sorry if unclear. They only make a 0 MOA Cant mount for the S&B 5-20 ultra short due to its limited tube length.

 

[GIXXER2000]

I have both Sphur and ETA-TAC both are very rugged and have never had an issue with either. I like having so MOA built into my mounts

 

[kblasser]

It's attractive to have a mount like this to move a scope from one rifle to another. I'm not sure, or understand how you maintain zero from rifle to rifle. Is this something that by trial and error figure out what the turret setting is, say 2 moa up for rifle one and zero moa up for rifle two. Someone please expound on how it's done.

 

[Ravenyzf-r6]

Same as when you change the barrel of a desert Tech SRS. The different caliber impact points will differ, but the change between them will be a constant. Pick one rifle to zero the scope on, then calculate what the second rifle needs to be zeroed and dial that in every time you switch the scope/mount.

 

[Covertnoob5]

It's attractive to have a mount like this to move a scope from one rifle to another. I'm not sure, or understand how you maintain zero from rifle to rifle. Is this something that by trial and error figure out what the turret setting is, say 2 moa up for rifle one and zero moa up for rifle two. Someone please expound on how it's done.

For a return to zero you first have to have a capable mount and a realistic perspective that even though a mount may claim a true return to zero that's not always the case.
I've had great luck with my era-tac and my spuhr. Even though the spuhr doesn't have qd lever, if you follow the torque directions you can get a repeatable zero.
Next, the actual process. Zero on the first rifle, and make sure you make a note of the turret settings in addition to the exact spot on the rail the mount is in. Then adjust the turret to get a zero on the second rifle but don't actually zero the scope, you just use the offset.
You can plug the offset into your ballistic calc so it'll account for it.


Better to have it and not need it, than to not have it and say oh shit.....

 

[Conrad]

Can anyone give me the front ring space on the 5-20 US? It is not listed in the schematic. However, schematic appears to be square with tube dimension so that would make the space 34mm = 1.34". Can I get verification? Thanks.

 

[dbransco]

Can anyone give me the front ring space on the 5-20 US? It is not listed in the schematic. However, schematic appears to be square with tube dimension so that would make the space 34mm = 1.34". Can I get verification? Thanks.

Here is a link to the manual for full dimensions;
http://www.schmidtundbender.de/phocadownloadpap/bedienungsanleitungen/pm/971-073-002-s.pdf

 

[Conrad]

Just found that also, thank you. Looks like 34.77mm = 1.369"....ARC Unimount is .069" too long, dang.

 

[dbransco]

Can someone provide torque specs for a Schmidt & Bender 5-20 Ultra short in a ERA-TAC one piece? I can't seem to find recommendations anywhere.

thanks.