I personally love my lead sleads I have two
I shoot over 100 rifles a year and a lot of magnums I have found that accuracy is not a problem with them in fact shooting club 300 yard bench rest .9 15 shot agg. With 300 wsm now club has made them illegal to shoot with by the way I use not added weight to them great when zeroing 12ga 3.5 mag in
Take a hammer and nock the back out of the rear stock holder, You might have to get a grinder and cut it but it will take the torque out of your lead sled and then it will recoil naturally. YOu can salvage what you have and it will work fine, you just need to modify it a little.