October 16th, 2007

U.S. Optics SN3 — $2800 Super Scope

People have already started asking about the U.S. Optics scope on Rob Hunter’s “BriTactical” rifle featured as the current Gun of the Week. This is no ordinary optic. It is a special “supersized” version of U.S. Optics SN3 T-PAL series, custom-built for Robert. The SN3 is offered with 30mm, 34mm, or 35mm main tubes. This is the big boy, 35mm, with matching U.S. Optics anodized rings. The front objective is upsized from the standard 44mm to a whopping 58mm. This provides enhanced low-light and twilight performance. The reticle is U.S. Optics’ own Mil Scale, allowing Robert to range-find targets reliably to 1000 yards and beyond. This is very critical because Robert will be using the scope in a Police/Military competition where he must engage multiple targets at unknown distances–and no laser rangefinders are allowed.

The big knob on top is one of U.S. Optics’ signature features. This is the EREK elevation turret. It allows Robert to run through his entire range of 1/4-MOA clicks in just two turns. If that’s not handy enough, a one-turn EREK knob is also available, but with wider click values. Like most U.S. Optics scopes, this unit is ruggedized and highly weatherproof. It features an illuminated reticle, handy side-focus parallax adjustment, and beefy metal construction. How much does one of these 5-25 power SN3 T-PALs cost? Well if you have to ask, you probably can’t afford it. Complete, with all the upgrades, the scope costs over $2800.00.

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October 16th, 2007

Neck-Turning Tip: Match Your Cutter Angle to the Shoulder

When neck-turning cases, it’s a good idea to extend the cut slightly below the neck-shoulder junction. This helps keep neck tension more uniform after repeated firings, by preventing a build-up of brass where the neck meets the shoulder. One of our Forum members, Craig from Ireland, a self-declared “neck-turning novice”, was having some problems turning brass for his 20 Tactical cases. He was correctly attempting to continue the cut slightly past the neck-shoulder junction, but he was concerned that brass was being removed too far down the shoulder.

Craig writes: “Everywhere I have read about neck turning, [it says] you need to cut slightly into the neck/shoulder junction to stop doughnutting. I completely understand this but I cant seem to get my neck-turning tool set-up to just touch the neck/shoulder junction. It either just doesn’t touch [the shoulder] or cuts nearly the whole shoulder and that just looks very messy. No matter how I adjust the mandrel to set how far down the neck it cuts, it either doesn’t touch it or it cuts far too much. I think it may relate to the bevel on the cutter in my neck-turing tool…”

Looking at Craig’s pictures, we’d agree that he didn’t need to cut so far down into the shoulder. There is a simple solution for this situation. Craig is using a neck-turning tool with a rather shallow cutter bevel angle. This 20-degree angle is set up as “universal geometry” that will work with any shoulder angle. Unfortunately, as you work the cutter down the neck, a shallow angled-cutter tip such as this will remove brass fairly far down. You only want to extend the cut about 1/32 of an inch past the neck-shoulder junction. This is enough to eliminate brass build-up at the base of the neck that can cause doughnuts to form.

K&M neck-turning tool

The answer here is simply to use a cutter tip with a wider angle — 30 to 40 degrees. The cutter for the K&M neck-turning tool (above) has a shorter bevel that better matches a 30° shoulder. There is also a 40° tip available. WalkerTexasRanger reports: “I went to a 40-degree cutter head just to address this same issue, and I have been much happier with the results. The 40-degree heads are available from Sinclair Int’l for $13 or so.” Forum Member CBonner concurs: “I had the same problem with my 7WSM… The 40-degree cutter was the answer.” Below is Sinclair’s 40° cutter for its NT1000 neck-turning tool. Item NT3140, it sells for $12.95. There is also a slightly more expensive 40° cutter for the NT3000 tool, item NT3340.

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