I am installing a TRG 42 in an Ashbury Precision Ordnance Saber-FORSST chassis and found a few small issues. I thought I would share in case anyone is thinking of doing this mod them self. Keep in mind APO stated that this should be installed by a gunsmith (which I am not, I just tinkerer) so it really isn't advertised as a "drop in". I have been able to complete this install with some simple hand tools and a little thought. Also keep in mind I have a sample rate of 1 therefore my findings are rather inconclusive as far as the big picture so YMMV. I have heard of 1 other install that was much better than mine, just the receiver interface mount was very tight but that person was able to install it with out cutting.
- The receiver interface mount would only go on about 1/4-3/8 of and inch. I found the left side of the dove tail was cut too tight. I used a triangular needle file and opened it up to fit. This took quite some time to get a proper fit. I would tap it on until it started to bind with a soft face hammer and then remove and look for the galling and file that down some. I repeated this until I had a snug (not tight fit).
receiver interface mount right side (did not have to open the dove tail up hardly any):
receiver interface mount left side (did not fit at all!!)
-The chassis tang opening was too tight for the action to fit in. I installed the recoil lug and indexed everything off that. I found the tang area was under cut for the action to fit. I had to open it up for proper clearance and the action to not bind. When I first tried to install the action it would not even set down into the chassis with the recoil lug in place. I don't have a pic of the action binding in the chassis and setting VERY proud.
Dark area just behind the rear action screw hole was the tightest spot:
Here is how much I had to remove for a proper fit. I cut a little and then tried the action again. Each time you remove the tight spot a new one shows up, do this until the tang now floats around the edges:
Action fitting properly
After all that was sorted out I went to install the monolithic pic rail. It sits on the receiver interface mount and over the fore arm and indexes using mortises and tenons and has 2 recoil pins that sit in predrilled holes. The pins were too long (by quite a bit).
Pins in the receiver interface mount, also receiver interface mount now properly fit to the action dovetail and fully installed:
Monolithic pic rail installed with the pins as shipped:
Monolithic rail with pins properly fit:
I am not complaining about this system just trying to give a heads up. I do however think this should have not required this much work to fit together properly. Especially when you factor in the price of this chassis!! I am interested to hear of others findings of how they fit weather they were with a TRG or an other action.
- The receiver interface mount would only go on about 1/4-3/8 of and inch. I found the left side of the dove tail was cut too tight. I used a triangular needle file and opened it up to fit. This took quite some time to get a proper fit. I would tap it on until it started to bind with a soft face hammer and then remove and look for the galling and file that down some. I repeated this until I had a snug (not tight fit).
receiver interface mount right side (did not have to open the dove tail up hardly any):
receiver interface mount left side (did not fit at all!!)
-The chassis tang opening was too tight for the action to fit in. I installed the recoil lug and indexed everything off that. I found the tang area was under cut for the action to fit. I had to open it up for proper clearance and the action to not bind. When I first tried to install the action it would not even set down into the chassis with the recoil lug in place. I don't have a pic of the action binding in the chassis and setting VERY proud.
Dark area just behind the rear action screw hole was the tightest spot:
Here is how much I had to remove for a proper fit. I cut a little and then tried the action again. Each time you remove the tight spot a new one shows up, do this until the tang now floats around the edges:
Action fitting properly
After all that was sorted out I went to install the monolithic pic rail. It sits on the receiver interface mount and over the fore arm and indexes using mortises and tenons and has 2 recoil pins that sit in predrilled holes. The pins were too long (by quite a bit).
Pins in the receiver interface mount, also receiver interface mount now properly fit to the action dovetail and fully installed:
Monolithic pic rail installed with the pins as shipped:
Monolithic rail with pins properly fit:
I am not complaining about this system just trying to give a heads up. I do however think this should have not required this much work to fit together properly. Especially when you factor in the price of this chassis!! I am interested to hear of others findings of how they fit weather they were with a TRG or an other action.
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