March 1st, 2015

Offset Scope Mount Helps Shooter with Vision Problem

offset scope base mountForum member Roy Bertalotto did a real nice off-set scope installation on a bolt gun to help a sight-challenged shooter. Roy explains: “A friend of mine shoots left-handed and has lost the sight in his left eye. I built him a scope mount so he can still shoot left-handed, but now use his right eye.” Roy’s fabrication work is impressive and we praise his efforts to help a fellow shooter stay in the game.

Roy bolted a plate to the existing scope rail on the top centerline of the Rem 700 action. This plate extends a few inches to the right. On the outboard end of the plate, Roy fitted a second scope rail, aligned with the bore. Weaver-based rings are then clamped to the outboard (right side) auxiliary rail.

offset scope base mount

offset scope base mount

offset scope base mount

Be Careful of Canting Issues with Offset Scope Installations
We’re pleased to see that Roy developed a solution for a shooter with an optical disability, but we want to stress that this is a specialized installation that can create some problems with point of impact shift if the gun is not maintained perfectly level. With the amount of horizontal offset (between the scope’s optical axis and the bore axis) built into this rig, if the rifle is canted, point of impact can shift rather dramatically. For a southpaw who is willing to adapt his/her shooting style, it may be better, in the long run, to learn to shoot right-handed if his/her right eye is the only good eye. Likewise, if a right-handed shooter can only see well through his left eye, he may benefit from learning how to hold the stock and work the trigger with his left hand. The shooter could still work the bolt with his non-trigger hand. Changing from right-hand to left-hand shooting (or vice-versa) may require a stock swap if the stock is not ambidextrous.

Permalink Gunsmithing 2 Comments »
August 20th, 2013

Burris Signature Rings — Calculating Actual Elevation Changes

Burris Signature Rings with polymer inserts are an excellent product. The inserts allow you to clamp your scope securely without ring marks. Moreover, using the matched offset inserts you can “pre-load” your scope to add additional elevation. This helps keep the scope centered in its elevation range while shooting at long range. Additionally, with a -20 insert set in the front and a +20 insert set in the rear, you may be able to zero at very long ranges without using an angled scope base — and that can save money. (To move your point of impact upwards, you lower the front of the scope relative to the bore axis, while raising the rear of the scope.)

Burris Signature Rings

Insert Elevation Values and Ring Spacing
People are sometimes confused when they employ the Burris inserts. The inset numbers (-10, +10, -20, +20 etc.) refer to hundredths of inch shim values, rather than to MOA. And you need the correct, matched top/bottom pair of inserts to give you the marked thousandth value. Importantly, the actual amount of elevation you get with Burris inserts will depend BOTH on the insert value AND the spacing between ring centers.

Forum member Gunamonth has explained this in our Shooters’ Forum:

Burris inserts are [marked] in thousandths of an inch, not MOA. To know how many MOA you gain you also need to know the ring spacing. For example, with a -20 thou insert set in the front and a +20 thou insert set in the rear, if the ring spacing is 6″, the elevation change will be approximately +24 MOA upwards.

Burris signature rings inserts

Here’s how we calculate that. If you have a 2 X 0.020″ “lift” over a distance of 6 inches (i.e. 0.040″ total offset at 0.5 feet) that’s equivalent to 0.080″ “lift” over 12 inches (one foot). There are 300 feet in 100 yards so we multiply 0.080″ X 300 and get 24″ for the total elevation increase at 100 yard. (Note: One inch at 100 yards isn’t exactly a MOA but it’s fairly close.)

Here’s a formula, with all units in inches:

Total Ring Offset
——————– X 3600 = Change @ 100 yards
Ring Spacing

(.020 + .020)
—————– X 3600 = 24 inches at 100 yards
6

NOTE: Using the above formula, the only time the marked insert offset will equal the actual MOA shift is when the center to center ring spacing is 3.60″. Of course, you are not required to use 3.60″ spacing, but if you have a different spacing your elevation “lift” will be more or less than the values on the inserts.

Permalink Optics, Tech Tip 11 Comments »
June 15th, 2012

Modular Low-Profile Competition Stocks from Wayne Young

Texas stock-maker Wayne Young has created an innovative modular stock. The fore-end side-plates bolt on to an aluminum sub-chassis so you can alter the width, or run an offset on either side of center. You can transform the stock from 3″ wide to 5″ wide in a couple minutes. Or, if you want to experiment with offset (i.e. having more fore-end width on one side of the barrel than the other side), you can simply remove a few bolts, and stack up the sideplates on one side.

Wayne's Gun Stocks

Wayne's Gun Stocks

The ability to quickly (and inexpensively) transform a stock from 3″ wide to 5″ wide is a definite plus for shooters who want to use the same rig in both F-Class and benchrest. You can run your rifle at max-legal 3″ width for F-Class, then bolt on additional fore-end “wings” to run at 5″ for bench competition. The 5″-wide stocks are now legal for 600-yard and 1000-yard benchrest, at both IBS and NBRSA registered matches. Those folks who have tried out 5″-wide stocks on Light Guns have been impressed with the results. The extra width stabilizes the rifle on the bags, reducing perceived twist (torquing) and hop. There is less “Rocking and Rolling”. With the gun torquing less, the tracking during recoil normally shows an improvement as well. (But we should say that, even with the standard 3″ width, these stocks track great.)

Wayne's Gun Stocks

Video Demonstrates Superior Tracking
How does a Wayne Young stock track? Straight and true — with virtually no hop. You can see for yourself. In the video below, Wayne shoots a test rifle chambered in .284 Winchester, a popular F-Class cartridge. The load is a 175gr Berger XLD bullet pushed at 3010 fps by Reloder 17 powder. That’s a stout, fast load — the recoil force easily meets or exceeds a typical F-Open match load. To better demonstrate the gun’s handling characteristics, Wayne deliberately shoots the gun free-recoil style — without gripping hard or shouldering the stock*. As you can see, the gun recoils straight back. The forearm and buttstock also slide perfectly in the bags, without “grabbing”. (Note: In the video, the rifle’s front bag-rider section is aluminum without polymer “wings”. This particular gun was built with a wider aluminum channel to fit a large-diameter, straight-contour barrel).

Stock Specifications and Design Features
Finished stocks weigh approximately 7 pounds, 4 ounces. If needed, stocks can be lightened to just under 7 pounds. Overall length is 36″. Length of pull is adjustable from 13 to 13.75 inches with standard two-way adjustable butt pad. The main chassis is machined from billet 6061-T6 (Tee Six) aluminum, while the fore-end chassis section is 6063-T5 (Tee Five). The black side sections, fore-end plates, and buttstock lowers are CNC-machined from high-grade HDPE, a rugged, chemically-resistant polymer.

The chassis for round actions features a “V-Block” seating area. There is a flat configuration for Panda and Stiller flat-bottom actions. With either the round- or flat-bottom configuration, actions can be mounted directly on the 1.25″-square aluminum chassis, using supplied action bolts. (Skim bedding is optional.) No inletting, pillar-installation, or stock finishing (painting) is required. Just bolt your barreled action into the chassis and head to the range.

Wayne’s stocks come with two-way adjustable butt-plate, adjustable cheekpiece, trigger guard, and all fasteners. If you consider all that standard equipment and the fact that Wayne’s gunstocks require no inletting and no finishing, these stocks are attractively priced. Wayne’s F-Open/Benchrest Stock, with 3″ fore-end, costs $499.00 plus $25.00 S/H. There is also a $499.00 F-TR version with a fore-end set up for bipod attachment. (Wayne produces an integral, adjustable and removable F-TR bipod for $75.00.) Add $100.00 extra if you want the aluminum components hard-anodized. With long actions or Savage actions, there is an extra charge to configure the central chassis to fit. For more information visit WaynesGunstocks.com or call (210) 288-3063 from 8:00 am to 4:30 pm Monday through Friday.

* If Wayne was shooting a .284 Win in an F-Class match, he would grip the gun and put some shoulder into it. But for demonstration purposes in the video, Wayne free-recoiled the rig so you can see how well it tracks with no holding or steering by the shooter.
Permalink - Videos, Gunsmithing, New Product No Comments »
May 24th, 2012

New to North America — GRS Laminated Stocks from Norway

Tikkashooters.com is now importing ergonomic field and tactical stocks crafted by GRS Rifle Stocks of Norway. These “Stratabond” Laminate wood stocks come in many colors — all with a gorgeous oiled finish. The GRS stocks come in three styles, plus a biathalon model, with an F-Class and Safari model to come. All styles are all drop-in inletted for most popular actions — not just Tikkas! GRS stocks feature Speedlock push-button adjustment for recoil pad position and comb height. All stocks come with a one-inch thick Limbsaver recoil pad.

GRS Stocks Norway Hunting

GRS Stocks Norway Hunting

Shown above is the Sporter/Varmint model, which comes in six colors. This design has a butt hook and the 6° grip angle for more comfortable hand positioning. As with other GRS stocks, the Sporter/Varmint model features quick, no-tools adjustability using a Speedlock system. Inlets are offered for Howa (SA, LA), Rem 700 (SA, LA), Sako (models 75, 85, L-579), and Tikka (models 55, 65, 595, 695, all T3 versions, including T3 RH, T3 LH, Varmint, Tactical).

GRS Stocks Norway Hunting

Next, shown above, is the GRS Adjustable Hunting model which comes in four colors: Black, Brown, Green Mountain Camo, and Royal Jacaranda. The fore-end is comfortable when shooting without a rest and the grip angle is canted 6° to provide a more ergonomic hold. Inlets are offered for Howa 1500 (SA, LA), Rem 700 (SA, LA), Sako (models 75, 85, L-579), and Tikka (models 55, 65, 595, 695, all T3 versions, including T3 RH, T3 LH, Varmint, Tactical).

GRS Stocks Norway Hunting

Last, but not least, is the GRS Long-Range Model, offered in six colors. This design is inspired by military sniper-type rifles. This stock is similar to the sporter/varmint model, but has a more pronounced butt hook with an integrated monopod with quick release and micro adjustment. The longer fore-end provides a better bipod platform and aids in balancing long, heavy barrels. Inlets are offered for Rem 700 (SA, LA, left/right), Rem 40X (single shot), Sako 75 (IV, V), Tikka T3 (Std, Varmint, Tactical).

Save $100 with Introductory Pricing This Month
For more information visit the GRS Stocks page on the TikkaShooters.com webstore. NOTE: Introductory pricing is available through May 31, 2012. The GRS Hunter and Sporter/Varmint stocks are currently priced at $697.00 fully inletted, including adjustable hardware. The Long-Range Model is currently priced at $897.00 fully inletted with adjustable hardware. Unless the intro pricing deal is extended, expect prices to increase $100.00 per model starting June 1, 2012.

Permalink Hunting/Varminting, New Product 11 Comments »
June 25th, 2010

Burris Signature Rings and Inserts on Sale at MidwayUSA

MidwayUSA is running a sale right now on Burris Signature and Signature Zee scope Rings and Pos-Align inserts. The Burris Signature Rings feature polymer inserts that fit between the scope tube and the ring itself. This protects the scope finish and also allows the scope tube to self-align within the rings. By using offset inserts with different thicknesses, you can keep your scope centered in its range of travel. You can also use the offset inserts to pre-load elevation into your scope, thus avoiding the need to purchase an expensive angled base for shooting at long ranges.

As examples of the current savings, Burris 1″ Signature Zee Weaver-Style Rings High Rings are marked down from $36.99 to $32.99. A set of Burris 1″ Pos-Align Offset Inserts (.005, .010 and .020) is now just $10.99, marked down from $14.99.

Permalink Hot Deals, Optics No Comments »