Adapt Armageddon GripChanger Bag for attachment to Picatinny rail for NRL22 barriers

[MLCM24]

The 1-1/4x3x7” Armageddon GripChanger bag factory mount is only available for ARCA rails and my Vudoo 22 has a Picatinny rail on the underside of the stock. Here’s a quick solution that uses a 7” section of a stainless steel ruler, a 1/4x2-1/2x7” aluminum bar, the American Defense BT56-L quick detach short adapter and tripod mount adapter plate (consists of BT56 and AD170S), and a 1/4x20 flat hex cap screw and 2 button head cap screws and nylon nuts. See picture showing parts and closeups of assembly holes which must be drilled. I hope assembly is self evident from the pictures. I remove my bipod and use this support for occasional stages of NRL22 matches. The center located screw was left slightly loose so it will slip, allowing the assembly to be aligned with smaller and odd shaped barricade openings or narrow surfaces such as the edge of a board or step of a ladder. It is narrow enough that bag assembly and firing point support can be gripped for stabilization.

 

[littlepod]

Does that ADM pic clamp not screw into the railchanger? Just remove the area419 arca clamp and bolt on the ADM pic one?

 

[MLCM24]

Does that ADM pic clamp not screw into the railchanger? Just remove the area419 arca clamp and bolt on the ADM pic one?

I didn’t have a railchanger piece but I did already have a AD-170S and aluminum bar and the bag only so it was less expensive for me to order the tripod adapter insert (about $20) and make the attachment. I hope someone can answer your question though. That would be a easy solution for the owner of the complete unit if attachments can be swapped out directly. Does anyone know?

 

[T.J.]

Nicely done. Suggest drilling two longitudinal holes so it can run both ways.

 

[MLCM24]

Here it is mounted longitudinal. See Photo.
There is only one screw (1/4x20) that
mounts the tripod/camera adapter to the aluminum base plate. The two threaded holes just lateral to the 1/4x20 screw are used for the two recessed flat head screws that hold the quick disconnect (AD170S) to the tripod adapter plate (BT56). There isn’t enough thread depth left to thread a additional screw up through the aluminum plate and into the adapter plate for further stability. That’s why I leave the 1/4x20 slightly loose so it functions with a sliding tension. This also gives some pan function to the assembly. Yes it does need readjustment if it loosens excessively but this is a accessory that isn’t used often and it can’t loosen too far because the screw head is wedged within the part that holds the bag. The photos help my explanation and show the threading within the two lateral holes.

 

[MLCM24]

Does that ADM pic clamp not screw into the railchanger? Just remove the area419 arca clamp and bolt on the ADM pic one?

This may be the answer to your question. Today the Area 419 website has the bare Rail Changer arm in stock. The description within the listing says “It will NOT work with other clamps, it will only work with the Area 419 ARCA clamp”.

Of course there is always the option to use the bare Rail Changer and drill new holes and tap or use a nut for screws inserted through the AD170S. For proper spacing and easier clearance for setting the lock lever, the BT56 adapter may still be necessary. If the latter is the case, the threads in the mount holes may need to be drilled out. The two hole mount option of course would not pan. The alternative would be a single hole for the 1/4-20 attachment tapped hole already in the BT56. For pan function a threadlocker would probably be needed since there is no block to keep the screw from backing out with repeated panning. Anyway, just trying to think through a possible design so the bare Rail Changer can be used. If anyone does try this, please let us know how it works and what other changes were necessary.

 

[MLCM24]

I’m still trying out different size bases. Using the same picatinny rail adapter, drilling a recessed 1/4” hole and cutting the screw to the correct length is all it takes. There is no limit to what will work. Here’s another. I used a 3/8x3-1/2x5-1/4” piece of aluminum. A 1/4” rubber pad was glued to the bottom (opening punched in it to allow access to the fastening screw). It can be used bare like this or a bottom bag can be added. The bottom bag is a small bag from Thunderbird Long Range I picked up from the awards table at a NRL22 match. Some Velcro strips keep the bag wedged in place. The idea should be clearer from the pictures. If someone else makes a base plate assembly, please post and tell us the firing point where the size and shape is most useful.

 

[littlepod]

I definitely applaud the work and design, but if you're truly shooting precision rifle events the goal is to have the bore/rifle as close to the bag for improved stability.

In your situation, why not just install an arca rail to your rifle stock?

 

[usafa77]

In your situation, why not just install an arca rail to your rifle stock?

Then you also get the advantage of using you bag the entire length of your forearm.

 

[Schütze]

Get the shemedium waxed bag from Armageddon with heavy fill. Empty about 1.5 cups out if it was as full as mine (keep the fill) easily adjustable volume. "Smack" the bag on the barricade or other surface and " smack" the frontend off your rifle in the bag. This allows
for the most stable position. Not my idea, learned from other good shooters. And if your rifle is no heavy enough in front, you can use your rail for a low scope ring with a round metal weight (diameter of the scope ring to clamp it).

 

[littlepod]

Get the shemedium waxed bag from Armageddon with heavy fill. Empty about 1.5 cups out if it was as full as mine (keep the fill) easily adjustable volume. "Smack" the bag on the barricade or other surface and " smack" the frontend off your rifle in the bag. This allows
for the most stable position. Not my idea, learned from other good shooters. And if your rifle is no heavy enough in front, you can use your rail for a low scope ring with a round metal weight (diameter of the scope ring to clamp it).

Agree. I run 98% unattached. I've only ran my attached bag on tiebreaker/timed stages.

 

[MLCM24]

Where I shoot, probably less that half of competitors have ARCA rails. Picatinny still predominates. As stated in the opening post, the intent of the post was to show a “quick solution” that would allow shooters to use the existing picatinny rail and construct other forms of support to replace the bipod for a limited number of firing positions. Just from informal conversation, it seemed that a plate was the most wished for item. I put this together just to show what could be done quickly and with less cost than replacing existing picatinny based equipment and attaching a rail that most frequently would not result in a professional fit because of the stock forearm contour. No “head to head” comparison was intended. Some shooters enjoy trying to innovate or substitute with what they already have.

I do thank the posters for pointing out the advantages of using ARCA equipment for NRL22 matches.

 

[MLCM24]

Get the shemedium waxed bag from Armageddon with heavy fill. Empty about 1.5 cups out if it was as full as mine (keep the fill) easily adjustable volume. "Smack" the bag on the barricade or other surface and " smack" the frontend off your rifle in the bag. This allows
for the most stable position. Not my idea, learned from other good shooters. And if your rifle is no heavy enough in front, you can use your rail for a low scope ring with a round metal weight (diameter of the scope ring to clamp it).

I actually use both the Short Action Precision sand filled cylinder and and sand filled Wiebad Cookie. Both are very heavy and smash down stable on a narrow or pointed barrier. They wedge securely between the plate or bipod (depending on stage I can’t always substitute plate for bipod if bag is used) and mag bottom metal on my short forearm stock. The sand is far more stable than a lighter fill.

 

[MLCM24]

Attached are several pictures showing the adapter attached to one end of a 4x7 plate. The plate is oriented extended back towards the shooter and with a flat bag attached. The stock has a short forearm and the bag almost reaches the magazine. From the bottom of the stock to the bottom of the bag is about 2-1/2”. This allows scope field of view clearance when firing from a folding chair seat and is low enough that I can fire prone from the top of a 5 gallon bucket or tire on its side. I have a similar setup using a much heavier 5x8 plate that feels like it has more stability. The most difficult item to find is a flat bag only 1” high. The 2” thick bag does not clear the back of chair opening. Most bags will need some fill removed. I had to use “sticky back for fabrics” Velcro strips on the bag. Just another way to help with stability on several NRL22 firing positions that were giving me a tough time!

 

[MLCM24]

Since my last post on this thread, Cole-TAC has marketed the Backbone Bag Frame. It is a Picatinny version that uses the American Defense mount. This may make making your own Picatinny flat plate/AD-170 mount previously described in this thread a mute point. However I wanted to use a substantially larger plate for hopefully more stability with a larger bag.

I used the Bison Tactical Skinny Udder Bag and started with a 1/4x7-1/2x7-1/2 aluminum plate and cut it to the dimensions and shape shown in the first picture. The American Defense AD-170S was mounted without using the tripod mounting plate used to mount the Picatinny adapter to the flat plate. I drilled and tapped for two #10x32x7/16 flathead socket machine screws to hold the adapter. Next I drilled and tapped for the four footman loops (1” opening) that hold the bag in place with webbing and Velcro. This time I used #10-32 oval head machine screws and had to file to length. Final placement was changed a little from the layout diagram so it was specific for the bag and the attached web straps. The second picture shows the final plate configuration. The next shows the bag in place. Keep the straps slightly loose so some pan function is available for multiple targets in a single stage. The remaining pictures show both how close the plate is to the stock and a idea about stability on a barrier and bench. It balances with my short stock if the placement surface is 3” or so and wider. It’s stable on the back of a chair but would need a regular length stock to give it the forward weight necessary to balance.

Having the bag and rifle as a single unit is convenient for the NRL22 matches I shoot. The bag never falls off the barrier and onto the ground! However if attachments need to be swapped during any single stage, this setup is not as fast to swap out as a ARCA based attachment. It can substitute for a bipod in many instances.

It is another option to choose from during matches.

 

[MLCM24]

When I use this udder bag attachment as shown in the previous pictures as a substitute for a bipod, it is a little too low for comfortably firing from a supported prone position on the ground. It is workable for supported prone from the bench. I wrapped a 2” Velcro tie around the legs to keep them from splaying and gained some 2-1/2” in height. This solved that problem and adds to options for strategy when transitioning through targets if the components of the stage allow. This way I don’t have to carry both a bipod and udder. See picture below.

 

[660grizzlyguy]

When I use this udder bag attachment as shown in the previous pictures as a substitute for a bipod, it is a little too low for comfortably firing from a supported prone position on the ground. It is workable for supported prone from the bench. I wrapped a 2” Velcro tie around the legs to keep them from splaying and gained some 2-1/2” in height. This solved that problem and adds to options for strategy when transitioning through targets if the components of the stage allow. This way I don’t have to carry both a bipod and udder. See picture below.

I just use a 1' section of 1/2" wall Armaflex (pipe insulation) for 2" pipe. Like a pool "noodle" that slides over the forend and doesn't need any hardware. Great for ladders or poking through barricade holes, and thin so you get low. That and a Game Changer is all I use, simple is good.

 

[MLCM24]

I’m intrigued. Low height barrier openings are a problem for me because my scope physically is taller than most, even with only a quarter inch clearance over the barrel/receiver. Is the Armaflex sufficiently compressible for a scope mounted this low? Your solution is simple and sure could take care of the problem with the the flat elbow pad I now use which easily slips out of position.