The Luth-AR MBA-3 Carbine Buttstock plays a central role in one of my current projects. Contrary to what you might see on this site, I do shoot more than just rimfire. So when setting up an AR for “extended range” fun, I knew it was going to need a Luth stock. Because the more time I spend behind custom rifles, the more I appreciate how important fit and ergonomics are. And the Luth-AR MBA-3 allows for a large range of adjustability. So it provides the precise fit I’m looking for.
Luth-AR MBA-3 Carbine Buttstock specs
This polymer buttstock is rated for .223 and .308 (although I have seen them on a few custom rimfire rifles as well) rifles using a standard six-position carbine buffer tube. Position on the tube affects length, but provides a lot to work with. Length of pull is 11-11/16 inches at the short end. Fully extended, LOP is 15-5/8 inches. In addition to the LOP adjustment, the buttplate can be adjusted up and down as well as side to side. Its cheekpiece has a full inch of adjustment as well. Overall, there is a lot of room to get just the right fit. Large aluminum knobs control the height and LOP adjustments, while a small hex wrench is needed for the finer buttplate adjustments. This mix of polymer and metal results in a stock that weighs just 19.2 ounces. All made in America, of course.
Luth-AR MBA-3 Carbine Buttstock features
Aside from all the adjustability, the Luth-AR MBA-3 Carbine Buttstock has some other important features. It’s set up to accept GrovTec QD cups (available separately). Below the socket is a bag hook. And on the bottom is a Picatinny rail for a monopod or even a bag rider. While other models of Luth stocks have a reversible cheekpiece, the MBA-3 is not reversible. But they covered that by making the cheekpiece wrap around to both sides, so it works for lefty shooters as well.
Somewhat unique when it comes to AR stocks, the MBA-3 fits most commercial and mil-spec buffer tubes. This is achieved by having an extra set screw that is tightened down once the buttstock is in place. Which means no rattles. And it’s small details like this that make me really appreciate the thought that went into this product. Rather than placing a set screw at 90 degrees from the buffer tube, and having it press into the tube, Luth took a different approach. The screw runs across the stock, and is used to “pinch” it to the buffer tube. And the small hex wrench required (which also fits the buttplate) is not only included, but is stored on the stock itself. I really like this design feature. Not completely “tool-less”, but the only tool required is securely onboard.
Stock options
No, this isn’t an investment opportunity, it’s about colors and pricing. The Luth-AR MBA-3 is available in black, of course, as well as FDE. Current price for either option is $159.95. For those that prefer black with an American flag on the cheekpiece, expect to pay an even $165.00. Luth does offer free shipping on orders over $175, and it’s easy enough to meet that figure. Ordering the full kit with buffer tube, buffer, spring, latch plate, and castle nut gets you there. Otherwise, add a GrovTec QD push button swivel and cup, or a couple of cups, and you’ve got free shipping. For what it’s worth, I much prefer those over the ones that require a separate nut and bolt to install. And Luth products were designed to use these GrovTec cups. It’s an easy choice.
Installation
That smart design extends to the installation and adjustment of the Luth-AR MBA-3. The pin for LOP adjustment is spring-loaded, and easy to use, hard to mess up. If you’re used to swearing at the adjustment lever of other buttstocks, you’ll appreciate Luth’s design that much more. That pin has a slot cut into it, and it has to be rotated so the slot lines up with a little tab, in order to fully extend it. Then the stock slides easily fore and aft. Once in place, rotate the pin and it’s nearly impossible to accidentally pull it out and adjust the stock by accident. Especially once the set screw is tightened. Recap: rotate pin, slide the stock on, and once it’s fully adjusted, lock it down for zero rattles.
Adjusting
With the stock installed, it’s time to get the adjustments down. My preference is to do that in the comfort of my home office, getting it set up while prone on the carpet. I can do the rest of my fine-tuning at the range, if necessary. This is because the adjustments are not infinitely variable. You’re not just turning a knob to change things. Each knob needs to be loosened, then the height or LOP changed in small fixed increments before the knob is tightened again. And there may be some significant trial and error when it comes to the buttplate.
To adjust the buttplate, remove the included wrench from the stock. For lateral changes, the two screws in the buttplate only need to be loosened a bit. For raising or lowering the buttplate, the screws will need to come out, so that the buttplate can be moved higher or lower. Not a super fast process, but once it’s all dialed in, it’s pretty much “set it and forget it” for me. Of course, since my scope isn’t yet mounted, I can’t do much more than get a rough setup at this time.
No range time, yet
I had previously used the Luth-AR MBA-3 on a bolt-action .308 in a chassis. And I liked it so much, that I decided my AR needed the same stock. The only difference is that this time I went with FDE (AKA tactical peanut butter) because a black rifle stock can get pretty hot in the Utah sun. Otherwise, it’s exactly like my other one. Which is great, because the new scope for this rifle hadn’t been mounted at the time I wrote this article. So I don’t have a full range report yet. But I can absolutely confirm that if you’re planning on spending any length of time behind this stock, it can and will provide a great fit.
Click here to check the price of the Luth MBA-3 at Opticsplanet.com
I’ll have my scope mounted this week, and weather permitting, will be able to shoot next weekend. So there will be a follow-up article once I’ve hit the range with this configuration. But I already know exactly what to expect. In the meantime, I think I’ve covered all the important details about this stock.
As always, I’d like to thank the folks at Luth for providing their Luth-AR MBA-3 Cabine Buttstock for my testing and evaluation. Although I already had one (in black), I’m looking forward to seeing if the FDE is a little more friendly in the hot sun. To check out the rest of their great stocks as well as grips and other accessories, visit Luth-AR.com.