DISCLOSURE: MARS is sponsored by Raven Rock Machine, however this fact was not taken into account when writing the review. I purchased the weight system with my own funds before I even considered them for a sponsor. This is an unbiased review where I point out both the highlights and shortcoming of the product.
The current trend in competitive precision rifle shooting is adding weight to the rifle. There are a few reasons for doing this:
- distributing the weight of the rifle to ease movement while getting into and out of positions
- balancing the rifle on barricades
- reducing recoil for faster follow up shots
- and, helping with the free recoil technique
All the new chassis offerings have options to add weight or even come with a weight kit. But what if you have an older chassis that does not have that option? This is where new entrepreneurs are trying to solve the problem. Enter Raven Rock Machine.
Raven Rock is a small one man shop, run by Dustin Holloman, that produces a weight system made to fit the Kinetic Research Group (KRG) chassis – the Whiskey 3, Bravo and X-Ray.
I first learned about Raven Rock from Scott Whitehead of BEST Steel Targets. I believe Scott came up with the idea but Raven Rock is be producing them.
The system consists of a brass forend weight and four steel butt plate spacers.
The forend weights 1 pound.
It’s really a beautiful piece of brass. I dinged it up while installing it, because at first I put it in backwards. I’ve since corrected the problem. The weight actually comes pristine.
The 304 stainless steel spacers are 1/4″ thick and weight .7 pounds each, meaning you can get a total 2.8 pounds if you use all four spacers.
Be careful of wanting to add too many spacers to get more weight and, thereby, sacrificing LOP. Get your proper length of pull first then replace with the steel weights.
The brass forend weight fits inside the bottom of the KRG aluminum backbone. Installation is simple:
- Remove your action.
- Unscrew the polymer KRG forend skin.
- Bolt in the weight with the included hardware.
The Bravo, Whiskey-3 and X-Ray chassis basically use the same aluminum backbone so this procedure is the same for all these chassis.
As you can see, there is plenty of room to use the KRG spigot with the forend weight installed.
The rear weight installation is even easier. The Bravo and X-Ray chassis uses a polymer spacer system to adjust the length of pull (LOP). The screw holes in the Raven Rock weights are the same as the KRG spacer/butt pad holes so you just remove your butt pad and replace the existing polymer KRG spacers with the stainless steel spacers.
The Whiskey-3 chassis uses a different system to adjust LOP. The butt pad assembly slides back and forth. There is a thumb wheel that locks in the LOP at different distances. However, the Whiskey-3 butt pad uses the same screw hole placement as the Bravo and X-Ray so the Raven Rock spacers will still fit behind the Whiskey-3 butt pad.
With the Whiskey-3, you can use both adjustment methods to get the LOP and balance you want. If you want more weight, set the thumb wheel LOP to its shortest setting and use the spacer system to extend the the LOP. If you want less weight, use less spacers and adjust the thumb wheel distance until you reach your desired LOP.
Raven Rock spacers are made to the adjustment intervals of the Whiskey-3, which is 1/4 inch. KRG polymer spacers are a bit longer at .365 inches.
I did run into one issue during the 20 min install. One of the holes in the KRG backbone was a bit smaller than the others. The included screws would not pass through it. This was a simple fix though because the backbone is made of aluminum. I took a cordless drill and enlarged the hole.
According to Raven Rock, KRG did not consistently cut their holes across their different versions. The current Whiskey-3 chassis is their generation 6 and along the way there was some variation to the hole placement. The Raven Rock forend weight was modeled after a Gen 6 backbone. Therefore there maybe some fit issues with other generations of backbone. Luckily this is not a big problem because aluminum and brass are soft metals and easy to modify, even for the home builder.
So far, I’m immensely enjoying the weight system. I’ve been able to dial in my balance point to exactly where I want it. And the additional weight is definitely helping with recoil management. There is a perceivable difference in getting subsequent shots back on target. It also balances much better.
The other big benefit is that I can easily change the weighted competition configuration to a lighter weight hunting/trekking configuration by removing the 2.4 pounds of mass. With the weights installed the rifle comes in at 16 pounds.
I was thinking about improvements or changes, but I could not really think of anything that would be practical for Raven Rock. I don’t think there is a solution to the hole spacing issue because it has to do with the variations in the KRG chassis itself.
There is no more room inside the backbone to add more weight, but you could add weight to the outside using the M-LOK slots. I believe all the KRG chassis have those attachment points. However, there are already some companies already producing these M-LOK weights, such as MDT. It’s not a unique idea and not specific to the KRG so I doubt it would be worthwhile for Raven Rock to produce them.
I’d like a way to add more weigh to the rear without extending the LOP. Maybe a weight in the butt stock or the grip. The problem with this is that the Bravo, X-Ray and Whiskey-3 have different stock designed. A single solution would not work for all of them. The spacer systems is the only universal fit.
Overall if you have a KRG chassis and you want more weight, I highly recommend this system. It’s simple and affordable. In the precision rifle gear race, that’s a unicorn. There may be some DIY individual fitting, but it’s really quite easy. There really is no other good solution for KRG shooters on the market right now. I’ve heard rumors that KRG will be coming out with some kind of weight system, which makes sense considering the trend. However, who know when that will be or if they will be able to keep them in stock.
Raven Rock has these weights available right now. If they sell out, there is a short turnaround time for them to machine a new batch. They are selling the forend weight alone for $75 + shipping. The entire system including the front weight and four rear weights is $120 + shipping. Contact Raven Rock Machine through their Facebook Page or at Ravenrocktoc@gmail.com. Let them know MARS sent you!