While my HK MR223 runs very smoothly with my 75/N540 load with the legacy suppressor, it has plenty of gas running factory bulk ammo.
Fortunately my gunsmith noticed that the adjustable HK gas block can be easily hand-fitted with a replacement gas port made by him. He could not make the new one operable with a hex key, but the slotted should work ok.
You just hold the metallic bolt open, pop out the old one and pop in the new one.
So far the new one still has too small holes, I inted to try out these two port sizes and record the bolt movement with slo-mo to make the best port sizes. Too bad I cannot get 3 settings into it to make:
-non suppressed
-suppressed Normal for my own loads
-suppressed Low for factory bulk
I will probably make it suppressed Normal and Low as I shoot only suppressed.
Not all factory ammo is as gassy, but especially the 55gr Geco bulk which I have stacked on..
Looking forward to modding it but getting it tuned will take some trying. I remember 1.1mm /0.043" being just around to get it to cycle with reloads suppressed and 0.055" to work without suppressor.
I have a flow-through suppressor too but the legacy suppressors are just so quiet and the sound itself is more pleasant. They also do not clog since there is nothing airways to clog which on the flow through gave some variance to gassyness. Yes, you can clean the suppressor but it get really old really fast.
Fortunately my gunsmith noticed that the adjustable HK gas block can be easily hand-fitted with a replacement gas port made by him. He could not make the new one operable with a hex key, but the slotted should work ok.
You just hold the metallic bolt open, pop out the old one and pop in the new one.
So far the new one still has too small holes, I inted to try out these two port sizes and record the bolt movement with slo-mo to make the best port sizes. Too bad I cannot get 3 settings into it to make:
-non suppressed
-suppressed Normal for my own loads
-suppressed Low for factory bulk
I will probably make it suppressed Normal and Low as I shoot only suppressed.
Not all factory ammo is as gassy, but especially the 55gr Geco bulk which I have stacked on..
Looking forward to modding it but getting it tuned will take some trying. I remember 1.1mm /0.043" being just around to get it to cycle with reloads suppressed and 0.055" to work without suppressor.
I have a flow-through suppressor too but the legacy suppressors are just so quiet and the sound itself is more pleasant. They also do not clog since there is nothing airways to clog which on the flow through gave some variance to gassyness. Yes, you can clean the suppressor but it get really old really fast.
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