According to MPA the only chassis that they currently produce that will accept a 1.25” diameter barrel is the ESR or Matrix. I would imagine that it would be difficult to have the proper clearance with the weight kit.
I have an MPA BA with a 1.25 staight barrel and a full internal weight kit. My gunsmith had to do a little carving on the end to get the barrel to fit.
I kinda figured the nubs would for sure have to go. If I’ve measure correctly, it’ll fit, but as you have already mentioned any flex at all will cause it to touch. The other two nubs on the bracing appear they’ll have to go also. Any idea if the weights themselves will touch?
I have an MPA BA with a 1.25 staight barrel and a full internal weight kit. My gunsmith had to do a little carving on the end to get the barrel to fit.