This is an announcement of a new service that LongRifles, Inc. is now providing. To my knowledge it’s not been done before by anyone other than a few experimental pieces that I did years ago which never went public. I’m calling it “surfaced chassis stock inletting”. (A mouthful as I lack a better term at this time so were stuck with it)
On every chassis stock I’ve seen the wedge style register is the most popular. It’s obvious that it works as there are lots of rifles shooting very well. That being said I feel there’s still room for improvement.
If we stand over the assembled rifle and imagine where the tangent contact points are at each side of the action/stock we can see that it ends somewhere along the tang’s tapering feature ahead of the rear guard screw. This means that the rear of the receiver is essentially hanging in space because the taper doesn’t allow for the wedge to bear any load once the screws are tightened. When the rear screw is tightened it uses this initial contact point between the receiver/stock as a pivot and leverages the front of the action off the chassis.
The point to take from this is that the receiver is not registering into the stock tension free. It’s being distorted to some degree. This is universally known in the precision rifle community as a bad thing as it can affect zeros, group size, bolt manipulation, feeding, and optics. As stated. We all know there are guns out there that shoot exceptionally well that use a chassis type stock. There are also an equal number of guns that would benefit from the modification. They are my target audience.
I recently CAD modeled the Remington action and wrote a surfacing tool path to machine the alloy chassis/bedding block on a number of “real world” M24 sniper rifles so that they would have a true 1:1 register with the action. Since it removes material, the receiver ends up lower in the stock approximately .04” of an inch. (Just over 1/32nd). On the M24’s this did not reveal any complications as the trigger shoe and magazine box still had sufficient clearance with the floor metal to function properly. We did have to intermittently trim a few guard screws to restore clearance with the bolt and fire control.
Surface machining is not a new process. It’s used extensively in a number of manufacturing applications. Mostly mold/die work and for a lot of aerospace applications. A number of common everyday items we all take for granted are surface machined or cast from a mold using surface machining techniques. (TV remotes, cell phones, etc) It’s a process that has really come of age now that computers have the number crunching ability to make millions of calculations per second.
The stock is fixtured in a 4 axis vertical CNC milling center. The program uses a single ball endmill to resurface the chassis in a spiraling motion. With each pass the tool steps over a programmed amount and finally completes the operation. For the M24’s I chose a .05” stepover as it was the best compromise between machine time and surface finish. As a result it leaves scalloped features with each pass. This is readily seen in the photos.
Performance:
These rifles are used as training weapons by an entity operating in the global theatre. Round counts per month range from 1500-1700 per gun. When we received the shipment the round counts on each gun covered a range of 11,000-16,000 since the last barreling done by another shop approximately 10 months ago.
The rifles are over 7 years old so if we use the last barreling cycle as the barometer were talking a total round count of 92,000-134,400 rounds on each weapon system. The documentation on each rifle is consistent with the math. The performance was also documented over the course of time beginning with the initial purchase, each barrel fit up, and ending with our evaluation once we completed the work we performed.
As reported to us by the owner, we have exceeded the standard in every capacity. The rifles shoot exceptionally well and its immediately evident by the scores students are now posting. The last class consisted of two operators. Both cleaned the course of fire during the final exam. This in itself isn’t all that impressive as it’s been done before with M24’s. What is remarkable is that they also shot perfect scores with the SR25’s that we were also tasked with servicing. (Another subject)
What this demonstrates to me is that the surfacing process we’ve developed IS improving the performance of the weapon system. What is interesting to note is that the guns are being shot with factory ammunition. They aren’t using exotic handloads. Each rifle retained the MIL-SPEC requirement. Meaning were not reinventing the wheel and running off and doing our own thing because we think its better. All of the factory parts are still being used. We’ve just improved upon them a little here/there and the system responded favorably.
With all this being said I’d like to take this opportunity to formally announce our new chassis stock surfacing service. If you send us your H/S precision stock we can now surface machine the inlet so that you never have to worry about bedding it again. As time allows we will expand this process to other stocks like the Manner’s mini chassis system and the line of stocks from Bell and Carlson. As I type this several clients are boxing up various examples of these to serve as test samples.
We are very excited about this as it’s emerged as a true solution to a challenge that has existed since these types of stocks first started to appear. We are also the first to offer this to the public. A Group Buy will be announced shortly for those interested.
C
On every chassis stock I’ve seen the wedge style register is the most popular. It’s obvious that it works as there are lots of rifles shooting very well. That being said I feel there’s still room for improvement.
If we stand over the assembled rifle and imagine where the tangent contact points are at each side of the action/stock we can see that it ends somewhere along the tang’s tapering feature ahead of the rear guard screw. This means that the rear of the receiver is essentially hanging in space because the taper doesn’t allow for the wedge to bear any load once the screws are tightened. When the rear screw is tightened it uses this initial contact point between the receiver/stock as a pivot and leverages the front of the action off the chassis.
The point to take from this is that the receiver is not registering into the stock tension free. It’s being distorted to some degree. This is universally known in the precision rifle community as a bad thing as it can affect zeros, group size, bolt manipulation, feeding, and optics. As stated. We all know there are guns out there that shoot exceptionally well that use a chassis type stock. There are also an equal number of guns that would benefit from the modification. They are my target audience.
I recently CAD modeled the Remington action and wrote a surfacing tool path to machine the alloy chassis/bedding block on a number of “real world” M24 sniper rifles so that they would have a true 1:1 register with the action. Since it removes material, the receiver ends up lower in the stock approximately .04” of an inch. (Just over 1/32nd). On the M24’s this did not reveal any complications as the trigger shoe and magazine box still had sufficient clearance with the floor metal to function properly. We did have to intermittently trim a few guard screws to restore clearance with the bolt and fire control.
Surface machining is not a new process. It’s used extensively in a number of manufacturing applications. Mostly mold/die work and for a lot of aerospace applications. A number of common everyday items we all take for granted are surface machined or cast from a mold using surface machining techniques. (TV remotes, cell phones, etc) It’s a process that has really come of age now that computers have the number crunching ability to make millions of calculations per second.
The stock is fixtured in a 4 axis vertical CNC milling center. The program uses a single ball endmill to resurface the chassis in a spiraling motion. With each pass the tool steps over a programmed amount and finally completes the operation. For the M24’s I chose a .05” stepover as it was the best compromise between machine time and surface finish. As a result it leaves scalloped features with each pass. This is readily seen in the photos.
Performance:
These rifles are used as training weapons by an entity operating in the global theatre. Round counts per month range from 1500-1700 per gun. When we received the shipment the round counts on each gun covered a range of 11,000-16,000 since the last barreling done by another shop approximately 10 months ago.
The rifles are over 7 years old so if we use the last barreling cycle as the barometer were talking a total round count of 92,000-134,400 rounds on each weapon system. The documentation on each rifle is consistent with the math. The performance was also documented over the course of time beginning with the initial purchase, each barrel fit up, and ending with our evaluation once we completed the work we performed.
As reported to us by the owner, we have exceeded the standard in every capacity. The rifles shoot exceptionally well and its immediately evident by the scores students are now posting. The last class consisted of two operators. Both cleaned the course of fire during the final exam. This in itself isn’t all that impressive as it’s been done before with M24’s. What is remarkable is that they also shot perfect scores with the SR25’s that we were also tasked with servicing. (Another subject)
What this demonstrates to me is that the surfacing process we’ve developed IS improving the performance of the weapon system. What is interesting to note is that the guns are being shot with factory ammunition. They aren’t using exotic handloads. Each rifle retained the MIL-SPEC requirement. Meaning were not reinventing the wheel and running off and doing our own thing because we think its better. All of the factory parts are still being used. We’ve just improved upon them a little here/there and the system responded favorably.
With all this being said I’d like to take this opportunity to formally announce our new chassis stock surfacing service. If you send us your H/S precision stock we can now surface machine the inlet so that you never have to worry about bedding it again. As time allows we will expand this process to other stocks like the Manner’s mini chassis system and the line of stocks from Bell and Carlson. As I type this several clients are boxing up various examples of these to serve as test samples.
We are very excited about this as it’s emerged as a true solution to a challenge that has existed since these types of stocks first started to appear. We are also the first to offer this to the public. A Group Buy will be announced shortly for those interested.
C
