Theoben Rapid Forum

machined with minus 25 MOA block/barrel alignment?

The reason I ask, looking at FX and dDS.. they have +30 rails, figured it was just for the long range boyos

None of my scopes align with optical centre, 4x sub-12 MK1 and MK2 and my FAC.
Whether I use OE mounts or a rail every scope needs around 25 moa dialed in to get OC on zero...most noticeably my Pard need the rear shimming because its waaayyy out.
Tried different barrels, swapped mounts around and ended up fitting Burris signature mounts to get FFP reticles central.
I had considered over-tightening of the barrel clamp but my mk2s are dead straight and apart from one iffy mk1 block the others show no bruising or contact wwith the rail.

Just one of those mysteries of the Rapid...
No mechanical reason to do that...
I had always thought it was due to the way the barrel is secured...
But on my Titanium Rapid.... Chip solved the problem by Machining a +25 moa Picatinny Rail!!

Stuart

Take a step back stop & think about it  ???
If the scope is optically centred LOS will/should be exactly parallel with the barrel, but depending on mount height will be 30-60mm above the bore.
Machining 30moa angles the objective down so that the optical centre LOS will intersect the predicted projectile trajectory closer to the predicted zero range
So the scope will require less adjustment away from optical centre in theory allowing greater accuracy.

If you are talking about the Theoben's Machining....
The angle is backwards...It is downward...
So I have seen some Rapid will run out of elevation adjustment before obtaining a Zero a a given distance..
So the REAR ring will need to be shimmed to be on target with a reasonable amount of elevation adjustment remaining!!

Stuart

Quote from: Ca_Varminter on May 21, 2024, 07:34:55 PMIf you are talking about the Theoben's Machining....
The angle is backwards...It is downward...
So I have seen some Rapid will run out of elevation adjustment before obtaining a Zero a a given distance..
So the REAR ring will need to be shimmed to be on target with a reasonable amount of elevation adjustment remaining!!

Stuart

yes found that my self Stuart,that's why when I do a barrel I always do it on the vertical pain and so any run out on the barrel is angled up towards the muzzle.as no barrel is perfectly true.
kevG