Adjustable Bag Rider for Stocks

[Rocketmandb]

Now that I've been getting my 37XC off the bench and out into the field, I've been running into issues with the stock and my rear bag. Not the least of which is that the sharp edges on bottom of the 3-way adjustable butt plate (see below) were ripping up my Protektor rear bag thanks to the heavy recoil.

I ended up making a wooden spacer fit to my length of pull to stop this. It works, but it doesn't really look all that great. So, when I was at the machine shop to pick up my extensions for my cheek riser, I showed them the butt plate and asked if they could make me an aluminum spacer to match. It would be expensive, but they could do it.

What does this have to do with an adjustable bag rider?

Well, I've been enamored with the notion of using an adjustable bag rider since I first started using my Phoenix bipod and Protektor rear bag. When I'm out on uneven ground, I have to do significant readjustment between shots. It's really a pain if I have to reach way forward to adjust the Phoenix. So, why not get an adjustable bag rider? It is straight forward for many chassis, but for stocks, it's not so easy. You have to have a way to mount it with enough room to allow the dowels to clear. This means some serious surgery on the stock IF you can even find someone to do it.

My thinking is that if I'm going to make a custom aluminum spacer so I can ditch the shitty looking wooden one I made, why not add a bracket to the bottom that can mount an ABR? So, that's what I'm going to try. I just ordered an ABR and will be taking everything over to the machine shop in a couple weeks. If this works out, I'll make some mods to my 300 PRC stock and try it there as well.

I'll post progress here.

 

[b2lee]

As you know...I'm a huge fan of Adjustable Bag Riders....I have them on most of my guns....anything that sits on a bench or used in competition. I don't have one on my hunting rifle because...well...weight..I want it light.

The combination of an ABR and a Phoenix has been great for me.

 

[Rocketmandb]

As you know...I'm a huge fan of Adjustable Bag Riders

Your fandom is part of the reason I'm taking this step.

I'm looking forward to trying this on my thumper. As mentioned above, if it works well on the 37, then I'll try it on my 300 PRC. The only thing with that rifle is that I'd be replacing the Manners' spacers and they use what amount to wood screws to hold them and the recoil pad in place. I don't feel comfortable putting any load onto those screws, so I think I'd have to put in some threaded inserts supported with epoxy and use something like a couple 10-32 screws.

On the plate in the 37, there is the massive .75" center post for support, so I don't think it would go anywhere. The only thing I need to do there is put a small block in to stop it from rotating.

 

[memilanuk]

So... just a thought here: if your adjustable butt plate is riding up between the ears of your rear bag, especially if it's tearing up the bag... you need to move the gun back or the bag forward, so that the toe of the stock is in the bag, not the butt plate.

I'm basing that off more than a few years of shooting F-class, where we used to run into the same problem, particularly when the stocks had (back then) more slope to the toe. The bipod would settle, the shooter would instinctively push the gun on the rear bag, using the slope of the stock vs. the slope of the bag to adjust the POI. You'd be shooting along, all tens and X's, and then get a weird off-call shot. Then you'd realize that the damn buttplate was up between the ears of the bag, and it wasn't recoiling the way it should. Or you'd be shooting clean, pause for a wind change, realize that the buttplate was up where it wasn't supposed to be, and then faced the dilemma of "do I change it now, which will almost certainly change my POI, or roll with it until it becomes a problem?"

One solution is to put a button or tab of some kind on the back or side of the toe of the stock. Doesn't have to be much, just something that you can push forward, feel it contact either the bag or the ears of the bag, and then ease back just a fuzz. Similar to how F-Open and BR shooters use the stop on their front rests. It's not so much a 'return to battery' feature, as it is a reference point so that you don't run the stock where it shouldn't be.

I'm not saying an ARB isn't a good idea as well... just saying it's not necessarily the solution you need based on what you described.

 

[Rocketmandb]

So... just a thought here: if your adjustable butt plate is riding up between the ears of your rear bag, especially if it's tearing up the bag... you need to move the gun back or the bag forward, so that the toe of the stock is in the bag, not the butt plate.

I appreciate the insights. Some notes:

- The only way I can move the stock back on the bag is to go to a shallower bag. The reason is that if I move it back any more than it is, the recoil is big enough that the back side of the grip hits my off hand where I'm gripping the stock. And with this frikkin beast, it hurts

- As to the ARB solving for this, adding the ARB was a bonus coming from my solution of making a spacer. I'd been looking for a way to incorporate an ARB and this gave me a way to do it.

Then you'd realize that the damn buttplate was up between the ears of the bag, and it wasn't recoiling the way it should.

Can I call you into threads where people don't believe that recoil dynamics affect POI?

 

[memilanuk]

The only way I can move the stock back on the bag is to go to a shallower bag.

This might be counterintuitive... but have you tried putting a pad, board or plate under the bipod to raise it up? I'm not familiar with the rules for ELR/ULR events; I know F-class has some specific language limiting the size and features of such devices to limit how much people can game the system... but sometimes raising the front end of the gun is easier than getting an entirely new bipod or rear bag.

The reason is that if I move it back any more than it is, the recoil is big enough that the back side of the grip hits my off hand where I'm gripping the stock. And with this frikkin beast, it hurts

Yah... I haven't shot like that in a long while. But I've had my knuckles rapped by a .308 or .300 in the past... can only imagine what one of the big boys would be like.

Can I call you into threads where people don't believe that recoil dynamics affect POI?

Newp. They can believe or not. Not my problem. Or, as one of my co-workers likes to say "not my monkey, not my circus"

 

[Rocketmandb]

This might be counterintuitive... but have you tried putting a pad, board or plate under the bipod to raise it up? I'm not familiar with the rules for ELR/ULR events; I know F-class has some specific language limiting the size and features of such devices to limit how much people can game the system... but sometimes raising the front end of the gun is easier than getting an entirely new bipod or rear bag.

I have a Phoenix bipod, which has a massive range for height adjustments.

 

[b2lee]

I have a Phoenix bipod, which has a massive range for height adjustments.

like 1k to 1 mile quickly with adjustment.

 

[memilanuk]

I have a Phoenix bipod, which has a massive range for height adjustments.

Yup, have one - though for FTR I have a lowering kit on mine

My point being, that if you are having to position the rear bag so far back on the toe of the stock to where the mounting flange of the buttplate is riding between the ears, something is not right (in my opinion). I'd move the bag forward, which is going to lower your point of aim. To raise it back up, without using up all the range of your bipod, use a front plate or board under it. Think of it like a coarse adjustment spacer or shim, that works in concert with the adjustment of your bipod. Like a canted scope rail, almost.

Or get ahold of Edgewood and get an extra low rear bag. They make 'em, or at least used to.

Some of this is, or can be, dependent on your body type or physique. At one point after talking with Derek Rodgers about his Edgewood bag with a reverse taper on it, I ordered one... but it turned out I didn't need one quite as low as he did, because, well, he's a skinny guy and I am... not

 

[Rocketmandb]

Yup, have one - though for FTR I have a lowering kit on mine

My point being, that if you are having to position the rear bag so far back on the toe of the stock to where the mounting flange of the buttplate is riding between the ears, something is not right (in my opinion). I'd move the bag forward, which is going to lower your point of aim.

Yeah, my problem is that if I move it any farther back, I'm rapping my knuckles every shot. I'm going to get an extra low rear bag when the bag rider piece gets made.

EDIT: I also have a thinner (front-to-back) bag that works, but I also feel it doesn't give the same support.

 

[memilanuk]

if I move it any farther back, I'm rapping my knuckles every shot.

Ah. Forgot about that. Most people I know don't use that kind of hold any more... for that, among other, reasons. Kind of one of those "if it hurts, stop doing that" / "Here's your sign" sort of things

I generally keep a selection of spacers in the range bag for under the rear bag as well. A 'dead bottom' sand bag/ring to help level things out - the nicer rear bags from Edgewood, SEB, etc. seem to have stiff enough bottoms that they don't really 'pooch out' like the old ones used to, so it's not so much to keep them from rocking, but they do make the bag sit just a little more solid. Then a couple leather spacers from Edgewood to accommodate different contour firing points. One of the worse was a few times @ Connaught where the firing mounds were uneven enough that one firing point I'd be in a damn hole, then the next one would be so crowned that I'd be using every spacer I had under both the front *and* back of the gun and still felt like it was almost high-centered in the middle. Fun times.

 

[Rocketmandb]

@b2lee
I got my bracket back from the machine shop and it looks like it will work really well.

I'll get to put it to the test next weekend, but so far just playing with it looks very promising. If you're wondering about the posts impacting the stock when the ABR is all the way closed, there are holes drilled where the rear two posts are - the forward post does not impact.

 

[Sigma]

remember these exist as well, i haven’t got to use mine thoroughly but they are very nice.

4AW Adjustable Bag BASES

Adjustable Bag bases Details for each base are listed with each product Bag set mentioned in video (Allen: Filled Front & Rear Shooters Rest)

4aw-store.myshopify.com

 

[Sigma]

also if you wanted something a little more rapid. terry dines (fusion pro) makes a rear bag elevator as well. its extremely nice but it only had elevation adjustment.

i dont think he has a website but he is on facebook

 

[Rocketmandb]

also if you wanted something a little more rapid. terry dines (fusion pro) makes a rear bag elevator as well. its extremely nice but it only had elevation adjustment.

i dont think he has a website but he is on facebook

I've seen similar, but I've never been a fan of the form factor. The adjustable bag rider is a lot more compact and, once installed, is part of the system, and not another piece of equipment you need to lug along. Additionally, adjusting something with an extra 15 lbs worth of rear bag on it vs. half that or so is a big difference - more work to adjust. The bag rider is smooth, simple, and easy.

 

[Sigma]

I've seen similar, but I've never been a fan of the form factor. The adjustable bag rider is a lot more compact and, once installed, is part of the system, and not another piece of equipment you need to lug along. Additionally, adjusting something with an extra 15 lbs worth of rear bag on it vs. half that or so is a big difference - more work to adjust. The bag rider is smooth, simple, and easy.

agreed they are clunky

 

[Rocketmandb]

Went out to BLM land to test out the bag rider. It worked very well - game changing...

EDIT: Also, I had a low bag from Protektor. It worked just okay. I don't feel like it gave me the support I needed for the 375. It also doesn't need to be as low as it is, so I'm going to see if they can custom make a half-height flat ELR bag.

 

[b2lee]

Went out to BLM land to test out the bag rider. It worked very well - game changing...

EDIT: Also, I had a low bag from Protektor. It worked just okay. I don't feel like it gave me the support I needed for the 375. It also doesn't need to be as low as it is, so I'm going to see if they can custom make a half-height flat ELR bag.

For ELR...and especially at a place like Black Bear SHooting Complex where you are doing high angle shooting.....a lot of us use stacked heavy rubber blocks under our rear bag to give us the height we need.

 

[CNC-Dude]

remember these exist as well, i haven’t got to use mine thoroughly but they are very nice.

4AW Adjustable Bag BASES

Adjustable Bag bases Details for each base are listed with each product Bag set mentioned in video (Allen: Filled Front & Rear Shooters Rest)

4aw-store.myshopify.com

I have 2 of them. They are better suited for prone shooting than benchrest, just so you know.....

 

[b2lee]

The funny thing is....the Adjustable bases are not allowed by rule in a lot of shooting disciplines...where as the ABR is allowed...since it is a part of the rifle.

 

[Taylorbok]

anyone else have pics of adjustable bag rider on a typical style stock.
Planning a build and I was wanting to use the new Manners ELR stock but apparently the adjustable bag rider version is only available for the larger actions, which I was going to use but plans changed.

Hoping to see what solutions people came up with. I don't want to raise the rear end up crazy high, it would be nice if there was a stock out there that would accommodate it decently.

 

[White Mamba]

The ABR on the Manners ELR will prevent the adjustable cheek piece from working its full range , they interfere with each other

 

[Taylorbok]

The ABR on the Manners ELR will prevent the adjustable cheek piece from working its full range , they interfere with each other

I'm assuming that means it won't go all the way down? I doubt that's an issue for most, usually need a tall cheek piece for big rails.

 

[White Mamba]

I'm assuming that means it won't go all the way down? I doubt that's an issue for most, usually need a tall cheek piece for big rails.

it will only go down as far as the adjustable posts of the ABR . They set them in the same spot, move the ABR down and you can lower the check piece, move it up you have to set the cheek piece higher

 

[Rocketmandb]

I don't want to raise the rear end up crazy high

I ended up getting a half-height Protektor made custom. It works really well and does not get you all that high with the setup I've got. In moderate (and gusty) wind last weekend, I had a string of 10 in a row at 1600, and hit 3 out of 10 at 2200 with my PRC. I think the ABR had a fair amount to do with that.

 

[Allthewatts]

How much slop do you get with the ABR? Very interested in getting on for the ACC chassis, but concerned about the rigidity of that design.

 

[Rocketmandb]

How much slop do you get with the ABR? Very interested in getting on for the ACC chassis, but concerned about the rigidity of that design.

Absolutely none with the fine-threaded one. Can't speak for the one with coarse threads.

 

[b2lee]

I get no slop....no rattle....fine thread. The ABR is one of the best purchases I've ever made.

 

[Sandow the Heretic]

I get no slop....no rattle....fine thread. The ABR is one of the best purchases I've ever made.

As long as the captive nut doesn't have much vertical play and the posts are in tight holes. It is a pretty stable mechanism. I used shoulder bolts in bronze bearing sleeves when I made one for an HS-50. Only limit is that as soon you have it you start wishing for a longer adjustment range on it lol.

-Alex

 

[b2lee]

As long as the captive nut doesn't have much vertical play and the posts are in tight holes. It is a pretty stable mechanism. I used shoulder bolts in bronze bearing sleeves when I made one for an HS-50. Only limit is that as soon you have it you start wishing for a longer adjustment range on it lol.

-Alex

I swear you looked at me funny when you saw me with my ABR 2 years ago at Unholy Alliance at Black Bear...and now you are telling me you run an ABR? I do love my ABR. Now I just need to find an ELR match on a weekend I don't work.

 

[Sandow the Heretic]

I probably gave you that look cause I had been machining and printing the bits for the HS-50 so recently. Personally I'm a bag squeezer at heart but with an ABR you can dial all the way down for the last target and build your position and with luck dial for the first target and never have to fuck with bipods or sliding an extra pad under your bag. More important now that my wife has caught the ELR bug cause she can't squeeze the bag under a heavy gun as easily as I can.

-Alex

 

[TreyMeTrey]

Now that I've been getting my 37XC off the bench and out into the field, I've been running into issues with the stock and my rear bag. Not the least of which is that the sharp edges on bottom of the 3-way adjustable butt plate (see below) were ripping up my Protektor rear bag thanks to the heavy recoil.

View attachment 8008335
I ended up making a wooden spacer fit to my length of pull to stop this. It works, but it doesn't really look all that great. So, when I was at the machine shop to pick up my extensions for my cheek riser, I showed them the butt plate and asked if they could make me an aluminum spacer to match. It would be expensive, but they could do it.

What does this have to do with an adjustable bag rider?

Well, I've been enamored with the notion of using an adjustable bag rider since I first started using my Phoenix bipod and Protektor rear bag. When I'm out on uneven ground, I have to do significant readjustment between shots. It's really a pain if I have to reach way forward to adjust the Phoenix. So, why not get an adjustable bag rider? It is straight forward for many chassis, but for stocks, it's not so easy. You have to have a way to mount it with enough room to allow the dowels to clear. This means some serious surgery on the stock IF you can even find someone to do it.

My thinking is that if I'm going to make a custom aluminum spacer so I can ditch the shitty looking wooden one I made, why not add a bracket to the bottom that can mount an ABR? So, that's what I'm going to try. I just ordered an ABR and will be taking everything over to the machine shop in a couple weeks. If this works out, I'll make some mods to my 300 PRC stock and try it there as well.

I'll post progress here.

Good Luck.

 

[Rocketmandb]

Good Luck.

Thanks - already taken them to the field a few times and they work great.

 

[Paul1262]

Is the ABR authorized for F class ? If yes, I would appreciate a specific reference in the rules. Thanks.

 

[A5scott]

I ended up getting a half-height Protektor made custom. It works really well and does not get you all that high with the setup I've got. In moderate (and gusty) wind last weekend, I had a string of 10 in a row at 1600, and hit 3 out of 10 at 2200 with my PRC. I think the ABR had a fair amount to do with that.

Can you post a pic of the half height Protektor bag?

Thanks,
Scott

 

[Rocketmandb]

Can you post a pic of the half height Protektor bag?

Thanks,
Scott

Not a close up, but it tells the story. I am quite happy with this setup. Will never own another ELR rig without an ABR.

The image is pretty high resolution, so I cropped around the rifle:

EDIT: You will notice that the Phoenix is pretty high. That position the range was ~1850 yards and the target was slightly elevated.

 

[A5scott]

Rocketmandb,

Thank you for that... that one is much more substantial, though I have used mine with excellent results

Scott

 

[Rocketmandb]

Thank you for that... that one is much more substantial,

I've got the one you show, but it wasn't providing the support I needed with my larger calibers. Worked fine on my 308 and down, but was a little squirrely on my 300, and no where close to what I needed on my 375.

When I called to order the custom bag, they were very apologetic - I was like, "no need to apologize. It works great on my smaller calibers, just not what I need for the bigger ones."

 

[A5scott]

This one is under a 338 Lapua, and it worked well.

Protektor seems like a great company that will make whatever you need.

Did you ever try one of their angled rear bags under your Mac Supermag? I know one pro shooter that competes and uses the angled Protektor under a McMillan Beast in 416 Barrett

Scott

 

[Rocketmandb]

This one is under a 338 Lapua, and it worked well.

Protektor seems like a great company that will make whatever you need.

Did you ever try one of their angled rear bags under your Mac Supermag? I know one pro shooter that competes and uses the angled Protektor under a McMillan Beast in 416 Barrett

Scott

I have one of the angled bags. Works great when there is no ABR, but not so much with it. I love their stuff, and they are much more accessible (availability, customer service, custom, etc.) than the few others out there offering similar products.