Sako S20 Owners, Recoil Moving Mounts Back?

[Euan]

Anyone with a S20 seen the same issue as below?

Have tried two of the Sako S20 base mounts and the 2 piece tier one mounts.
When tightening the bases/mounts to the action I'm pushing firmly forwards making sure the front of recoil lug is firmly against mating face of the picatinny slot but once I start firing on all 3 variations of mounts they start sliding/moving rearwards no matter how tight you tighten the screws. Got me head scratching as to why this would be happening but the rifle is currently away back to GMK awaiting update just interested if any other S20 owners mounts are in the opposite rearwards recoil lug position to a normal guns recoiling wanting to move everything forwards from firing.

 

[Steff]

Are you using a muzzle break? This can sometimes turn normal physics around.

 

[CarlW]

Are you using a muzzle break? This can sometimes turn normal physics around.

I accidentally dropped my muzzle brake last week and put a hole in the ceiling.

 

[Euan]

Are you using a muzzle break? This can sometimes turn normal physics around.

Sorry should have said this has happened with moderator on. Freyr and Devik and Wildcat Evo happens with both

 

[Steff]

I accidentally dropped my muzzle brake last week and put a hole in the ceiling.

Better talk to your architect.

 

[User00040]

Anyone with a S20 seen the same issue as below?

Have tried two of the Sako S20 base mounts and the 2 piece tier one mounts.
When tightening the bases/mounts to the action I'm pushing firmly forwards making sure the front of recoil lug is firmly against mating face of the picatinny slot but once I start firing on all 3 variations of mounts they start sliding/moving rearwards no matter how tight you tighten the screws. Got me head scratching as to why this would be happening but the rifle is currently away back to GMK awaiting update just interested if any other S20 owners mounts are in the opposite rearwards recoil lug position to a normal guns recoiling wanting to move everything forwards from firing.

Check the actual specifications of the mounts and rail/attachment.

There are Weaver, picatinny and STANAG.

See here: Understanding the difference between: Weaver, Picatinny, Nato Standards

 

[Euan]

Check the actual specifications of the mounts and rail/attachment.

There are Weaver, picatinny and STANAG.

See here: Understanding the difference between: Weaver, Picatinny, Nato Standards

Appreciate the information but the two S20 mounts I have tried a specifically designed for this rifle

 

[Doric]

Anyone with a S20 seen the same issue as below?

Have tried two of the Sako S20 base mounts and the 2 piece tier one mounts.
When tightening the bases/mounts to the action I'm pushing firmly forwards making sure the front of recoil lug is firmly against mating face of the picatinny slot but once I start firing on all 3 variations of mounts they start sliding/moving rearwards no matter how tight you tighten the screws. Got me head scratching as to why this would be happening but the rifle is currently away back to GMK awaiting update just interested if any other S20 owners mounts are in the opposite rearwards recoil lug position to a normal guns recoiling wanting to move everything forwards from firing.

Perhaps the machine screws are a little long and bottoming in the blind threaded hole. Worth investigation.

 

[Euan]

Perhaps the machine screws are a little long and bottoming in the blind threaded hole. Worth investigation.

There is no blind hole to bottom out on

 

[User00040]

Appreciate the information but the two S20 mounts I have tried a specifically designed for this rifle

Sorry but unless you bought Sako's own system I'm not sure you can say that.

Sako advertise that they have made a mount specially for it.

 

[Euan]

Sorry but unless you bought Sako's own system I'm not sure you can say that.

Sako advertise that they have made a mount specially for it.

Yes correct mate and I have two of them in the picture one in 0moa and other in 20moa and both start moving rearwards

 

[User00040]

Yes correct mate and I have two of them in the picture one in 0moa and other in 20moa and both start moving rearwards

No worries, I misread your original post.

Apologies!

 

[Euan]

No worries, I misread your original post.

Apologies!

No sweat mate, head scratch though

 

[Steff]

This effect can sometimes be observed on heavy caliber semi autos. The impulse of the receiver is more substantial than the recoil and it is working in the opposite direction. The same can happen with muzzle breaks and even moderators. Hence my question above.

 

[TURNBOLT]

My mate had this same problem with optilocks on a Sako 85 laminate Hunter 85 in 243W.gunsmith drilled a hole through the bases and put a pin through into a hole on the rifle top rail.He had done one or two before! The gunsmith said it was caused by inertia recoil from the moderator.

 

[rem284]

The inertia recoil from the rifle fitted with a sound moderator was blamed for the circlip coming off the Sako 75 trigger pin. It was also the reason why some scopes were have the reticules breaking.

 

[Lateral]

I accidentally dropped my muzzle brake last week and put a hole in the ceiling.

Arr, but was the brake still attached to the barrel

 

[takbok]

@Euan maybe it's worth trying to push the mounts rearwards then tightening. It doesn't sound like the rifle is at fault. Was it causing accuracy problems?

 

[Euan]

@Euan maybe it's worth trying to push the mounts rearwards then tightening. It doesn't sound like the rifle is at fault. Was it causing accuracy problems?

Correct me if I'm wrong mate but doesn't that kind of recoil damage the internals of scopes as they're not designed for kind of recoil? I've got a 3k swarovski scope on top and I don't want to be knackering that up because of it

 

[takbok]

Correct me if I'm wrong mate but doesn't that kind of recoil damage the internals of scopes as they're not designed for kind of recoil? I've got a 3k swarovski scope on top and I don't want to be knackering that up because of it

I doubt it. Use of moderators and this type of mount is commonplace these days. Nonetheless it will be interesting to see what Sako says - please update us.