Why don’t scope mount manufacturers list the largest objective bell that will clear the gun?
by B.B. Pelletier
Paul sez I’ve noticed that certain specifications on scope mounts is near impossible to find on the Pyramyd website and on the internet in general. In particular, the maximum objective sizes for certain mounts, like the B-Square 17101. I know its a good idea for people to call with their tech questions, however when assembling a wishlist at 2 am its a bit difficult. Even the B-Square website has no specs on their models. Pyramid would be the ONLY website with this info if they decided to add it to the description. I’m guessing that ther 17101 is for objectives up to 44mm, and the High Mount version 17701 is for 50mm and above. I’ve already emailed Pyramid on this, I just thought I’d share it with the readers who may also be scratching heads.
I have heard this same question many times, so today I would like to address it. Why don’t mount manufacturers (or dealers, as Paul mentioned) list the largest scope objective bell that will clear a rifle with each mount?
The reason they don’t do it (in fact, cannot do it) is because all guns are not made the same. Let’s look at some dramatic examples that illustrate my point.
Spring rifles with straight receivers
First, let’s consider a spring rifle that has dovetails cut directly into the spring tube. The scope will clamp directly to the spring tube, which means that the height of the scope mount is all that raises the scope objective bell above the receiver. Look at what happens when that kind of gun gets scoped.
This Bug Buster 2 has a 32mm objective bell, but look how close it comes to the top of the receiver on this Hammerli Storm. With this gun, and if you use no other scope bases, you need high rings to go to a 40 mm objective.
I’m going straight to the opposite extreme, when I show you a Talon SS. All AirForce rifles have a raised scope rail that elevates the scope far above the receiver. You can mount a scope with a 56mm objective in low mounts on these rifles and still have room to spare.
The scope rail on this Talon SS raises the scope high! The reason the rifle has the AirForce TriRail and the B-Square Ultra High rings is for the shooter’s preference, but the scope’s 50mm objective would clear with ease – even with low mounts.
So, each type of gun has a different scope height allowance, if you want to talk about it that way. And, that’s before we throw in accessories that also raise the scope, like the AirForce TriRail shown above.
If this was such an important issue that the feds got involved, there could be standards like “measured from a straight receiver” in every scope mount ad. Then, the buyer would have to decide if his gun had a straight receiver or a raised one. If raised, how much?
But, it isn’t that important, so the airgun industry will just have to keep plugging along. Dealers will have to answer these questions because no table can be constructed to fit all the circumstances.