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Discussion Starter · #1 ·
I found a thread on the 16 but I need to know the standard gas screw size on the 17 and then the size on the 13" CQB barrel

Thanks
 

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I just swapped a 1.30 in mine this morning for a 1.40.

With 1.30 it would cycle fine with Horrnady 308 but short stroke bad with Wolf 308. I thought I remembered that Silver Bear would cycle the 1.30 OK but that might have been my 16" barrel assembly.
 

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Discussion Starter · #3 ·
I just swapped a 1.30 in mine this morning for a 1.40.

With 1.30 it would cycle fine with Horrnady 308 but short stroke bad with Wolf 308. I thought I remembered that Silver Bear would cycle the 1.30 OK but that might have been my 16" barrel assembly.
So you have a 1.40 with a 13" barrel working OK?
 

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Well I haven't tested it yet but from experience with the short stroking I thought I had to go up 2 sizes to get it running with the weak Wolf ammo. Next time I go out shooting will tell for sure.

And 1.30 worked with Horrnady 308 so it can really depend on what ammo type you want your rifle tuned for and how reliable you want; going up an extra gas screw size over reliable will help ensure reliability in adverse conditions.


My advise is to buy a bunch of screws and test them out until you find what works best for your needs.
 

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I found a thread on the 16 but I need to know the standard gas screw size on the 17 and then the size on the 13" CQB barrel

Thanks
Mine came with an OEM 1.5mm screw. After the barrel was cut down to 14.5" it failed to cycle at all and I had to buy larger GCS sizes. 1.6 resulted in a few failures to lock back, but 1.7 was ok. Maybe 1.65 would have been ok too but I didn't feel like testing any further.
 
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