Paul Austin tests the new Burris XTR Signature Scope rings, finding a reliable alternative to the traditional “20 MOA rail” addition

MOA adjustment can be a tricky and potentially expensive business. If you really want to reach out, the traditional method is to add a 20 MOA rail to your rig. It’s a fairly permanent addition and in some cases an ugly one that certainly does the job but often increases scope height while doing little for the aesthetics of a classic sporter.

If your scope is ‘on the stops’ (never a good idea anyway), a dedicated rail has been the only choice. Until now! It appears Burris have finally come up with a flexible (and aesthetically pleasing) alternative with the XTR Signature Scope Mounts.

I’ll be honest, I was a little sceptical at first. The prospect of sleeve inserts in scope rings didn’t fill me with confidence. Long-range shooters are particularly fastidious about scope rings, with some using dedicated tools to lap scope rings to achieve the ultimate in precision.

Burris have gone for an unconventional approach by adding polymer inserts into ball and socket style rings, in a similar manner to some modern torch mounts. It’s certainly ingenious, but is it accurate? The basic principle is simple. Each set of rings ships with four pairs of inserts, and you simply mix and match them to create the required elevation in MOA.

The range of adjustment can be dramatic, ranging from just 5 MOA all the way up to a whopping 40 MOA. To put that into context, the 40 MOA set-up with the rings spaced at 3.5” delivers a massive 54.24” of elevation at 100 yards.

Set up is pretty straightforward. Let’s say you want 20 MOA. In that case, you add a 0 MOA insert on the rear ring and a 20 MOA on the front. The Pos-Align offset inserts come in matched pairs with a + and a – on each side, the former being thicker and the latter thinner. To create a 20 MOA adjustment, you simply drop the – half in the base of the ring and its thicker counterpart in the top ring.

Because the inserts are essentially free floating prior to being tightened down, they can pivot slightly, ensuring there’s no bending stress on the tube, which is another bonus of the system and a big improvement over traditional shimming.

You can also offset the shims themselves at 45° to add windage adjustment if required. This could be particularly handy for 30mm-tubed digiscopes, which can be notoriously tricky to mount and align.

The rings ship in a very rugged case and the whole package feels high quality. The instructions are straightforward and there’s a handy chart listing MOA levels with a combination of shims and ring distances, the primary goal being to get your scope back into its sweet spot at extended range.

I’ve used the rings for several months on my .243 with no loss of zero. I also gave them a spin on my .270 for a bit of additional recoil punishment and they’ve performed flawlessly.

The only issue I found was in the width of the mounts. With six screws per ring, they eat up a fair bit of the tube’s real estate, which can make adding additional tube-mounted accessories such as Picatinny rails and torch mounts a bit tricky on shorter optics. That aside, I can’t fault them. An ingenious, reliable and elegant solution to a tricky problem.

Prices: 30mm £110; 34mm £145

www.gmk.co.uk