Authentic Atlas CAL Gen2 bipod -- simple mod to make the tension/lock lever work like I expected it to

[stovepipe]

I bought an Atlas Cal Gen2 bipod many months ago. My specific model was the CAL BT69-LW17. I was very dissapointed with the way the podlok lever worked. I expected the tension to increase/decrease as I turned the lever and for the bipod to hold whatever tension I set it to. Atlas CAL bipods don't do what I expected, at least not from the factory. The good news is that I came up with a simple mod to make it work the way I wanted it to.

Here's the short version of what I did:
1. Unscrew/remove podlok.
2. Unscrew/remove nylock nut.
3. Remove belleville washer.
4. Remove brass flat washer.
5. Place new belleville washer onto compass bolt with the open cup side facing towards the podlok.
6. Screw podlok on.

I did not put the brass flat washer back onto the bipod -- it no longer has a purpose.
I did not put the original bellevelle washer back onto the bipod -- it no longer has a purpose.
I did not put the nylock nut back onto the bipod -- it no longer has a purpose.

Finding a new belleville washer (spring disk) to put on the bipod required some measuring and a lot of shopping and some trial-and-error.
There are two types of belleville washers I bought from McMaster-Carr that work well. One is stainless steel and the other is a nickel alloy.
The stainless steel has a smoother finish and a lower max pressure than the nickel alloy.
If my rifle was not so top-heavy, I would use the stainless steel. But my rifle is very top heavy, so I use the nickel alloy.
According to the description of both of these belleville washers on McMaster-Carr's web site, they can be compressed to completely flat (pancaked as we airgunners would call it) and still come back to their original shape and retain their "springyness".

Here are the part numbers and descriptions of the two types of belleville washers (spring disks) from McMaster-Carr:

Stainless steel:
9713K19 Corrosion-Resistant Belleville Disc Spring for 1/4" Shaft Diameter, 0.255" ID, 0.75" OD, 0.0360" Thick, Packs of 3

Nickel alloy:
97125K119 Extreme-Temperature Belleville Disc Spring for 1/4" Shaft Diameter, 0.255" ID, 3/4" OD, 0.04" Thick

Here are a few things that are worth noting in no particular order:

The base of the belleville washer will rotate around the base of the compass bolt and will wear on the aluminum block initially. After some use you probably won't notice much, if any, additional wear. My BT69-LW17 has a round (not keyhole-shaped) hole at the base of the compass bolt, so the wear is even. I don't know how it will wear on the older CAL bipods that have a keyhole-shaped hole around the base of the compass bolt.

Although CAL bipods don't have a hard lock (it's just tension), this mod makes it a LOT easier to crank down to max tension with just normal adult male hand strength without bruising or bashing knuckles or curse words.

Other people in the world may have come up with this same idea, but I haven't found anything like it on the internet. Sometimes the same problem is solved independently by many people who all come up with the same solution.

Don't think you're helping anything by putting the brass flat washer on under the belleville washer or by stacking a bunch of belleville washers. You want as many podlok threads to be engaged as possible. Adding material under one of the single belleville washers I recommend is only decreasing the number of podlok threads that are engaged when you are cranking down the tension to maximum.

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[Ta-Ta Toothie]

Funny, I have a BT65-LW17 Gen. 2 and the Pod-Loc is absolutely perfect. Smooth, stays where you put it and doesn't loosen up. Now my ACCU-TAC WB-4 pivot lock stinks. I wish I could adapt the Pod-Loc on it.

 

[stovepipe]

Here is an elaboration on my original post and a few pictures. The "how to" is in the original post. Here I just want to explain how this mod changes the behavior of the Atlas CAL Gen 2 bipod. The CAL Gen 2 bipod has a small belleville washer that can be compressed by a nylock nut internally. This is the "preload" tension. During use of the bipod, the only additional tension you can add to the preload tension is with the Pod-Loc lever. As you rotate the Pod-Loc lever clock-wise to tighten it from it's floppy loose position, it instantly stops when it contacts the brass flat washer. This gives the operator about 1/16 of a turn to go from no-additional-tension to maximum tension. When loosening the Pod-Loc lever from maximum tension, the operator must try to turn the lever counter-clockwise with increasing effort until the lever breaks loose. The lever breaks loose suddenly from max tension to no tension and commonly results in the operator bashing knuckles on the nearest hard object. In my case, the nearest hard object is usually the rough end of the quick-disconnect lever of the picatinny attachment.

The behavior I hoped for when I bought this bipod was a long throw of the lever that would smoothly increase tension from zero to max with about a 180 degree turn of the Pod-Loc lever, which is what this mod does. This mod turns the Pod-Loc lever into an externally-adjustable on-the-fly preload tension adjuster. It still "locks" as tight as the original from-the-factory bipod.

Here's a picture of my bipod with no Pod-Loc, no nylock nut, no belleville washer, and no brass flat washer. The camera really exaggerates the wear marks.

Here's a picture with a new belleville washer. The open cup side of the washer is facing up in this picture.

Here's a picture of the Pod-Loc screwed on, but not far enough to touch the washer yet.

Here's a picture of the Pod-Loc screwed on just enough to touch the rim of the belleville washer.

Here's a picture of the Pod-Loc screwed on tight enough to pancake the belleville washer.

I don't bash my knuckles anymore when loosening the lever from max tension.

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[stovepipe]

Here is the final mod to my Atlas CAL Gen 2 bipod -- the Pod-Loc lever really works the way I want it to now. The posts above talk about getting smooth externally-adjustable tension all the way from no tension to max tension -- and it works great (for me best with the Nickel alloy bellville washer). However, tension is not the whole "fix" for me. I also needed more friction. I found the answer on the Snipers Hide forum. The thread is titled "My solution to stiffen up Atlas bipod cant". The gentleman there explains it all in the first post of the thread. So I ordered the Carbontex drag washer size 8** (less than 4 bucks including shipping) like he said and swaped the soft plastic drag washer that comes on the Atlas with the Carbontex (carbon fiber) drag washer and I'm totally happy with the way the Pod-Loc lever works on my bipod now.

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[stovepipe]

Funny, I have a BT65-LW17 Gen. 2 and the Pod-Loc is absolutely perfect. Smooth, stays where you put it and doesn't loosen up. Now my ACCU-TAC WB-4 pivot lock stinks. I wish I could adapt the Pod-Loc on it.

I'm surprised that your Accu-Tac is not "happy". I've never used an Accu-Tac, but I thought they were built like tanks. I almost sprung for the Accu-Tac, but I needed a lighter weight bipod with more height adjustablility and I definitely needed the legs to be able to fold up fully forward and backward, so I got the Atlas Cal. The only dissapointment with the CAL was the way they only utilitized the pod-loc lever as an attempt to lock it in place once you get on the bubble. But I'm definitely not bashing the CAL. The two simple and inexpensive mods I made transformed the CAL's pod-loc into perfection (not a word I use often). One of the nice things about my mods is that they are totally reversable, so there is no harm in trying them. The Nickel alloy belleville washer is kind of spendy -- I think $9 plus another $9 for shipping. The carbon fiber drag washer was only about $3.84. Man... what a difference! I'm not the only one that uses my FX Maverick 30 cal sniper with this bipod, and we both went from being dissapointed with the CAL to loving it after the mods. Sorry I'm getting so wordy -- I'm just excited because I was close to selling the CAL -- that would have been a mistake.

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[Ta-Ta Toothie]

The Accu-Tac is rock solid, just the pivot system stinks. I had to modify that to make it acceptable. Bronze washers and a few spring washers. Atlas definitely has the better pivot, but the legs have plenty of slop.

 

[stovepipe]

The Accu-Tac is rock solid, just the pivot system stinks. I had to modify that to make it acceptable. Bronze washers and a few spring washers. Atlas definitely has the better pivot, but the legs have plenty of slop.

Yes, the Atlas Cal legs have a lot of play in them, unlike the Accu-tac. Even though I haven't used an Accu-tac, it's obvious that the legs on it are going to lock rock solid because of the "wedge" engagement between the legs and the body. The legs of the CAL work out well for me though, because the small amount of recoil from my maverick gets taken up by the leg "slop" in a controlled manner without the feet actually sliding back over rough ground (which would bump me off target).

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[Ta-Ta Toothie]

They both have their quirks. Good writeup though.

 

[stovepipe]

Thanks ta-ta toothie. Nice chatting with you.

I have an extra Nickel alloy belleville washer that I won't need and 2 extra stainless steel belleville washers that I won't need. I don't have an extra carbon fiber drag washer, but if anyone wants the bellevilles, just PM me and I'll mail 'em to you.

EDIT: I've already sent the Nickel alloy belleville and one stainless steel belleville to an AGN member (will later today). I have one more stainless steel belleville that I can send to the next person that wants it.

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[stovepipe]

Here's a clunky illustration showing the correct orientation of the belleville washer in relation to the Pod-Loc for this mod.

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