Initial Review - Sterling Arms International (SAI) R9 Mk1, 9mm PCC

Here is a TFBTV article on the Mec-Gar's metal Glock mags that are used in the latest Staccato pistols. They may meet Sterling's requirements for dependability compared to polymer Glock magazines for the R9, while allowing people to use their stockpile of polymer Glock mags for non-critical situations:

TFBTV said:
 
In the event more NR rifle calibre firearms returned to common use, but the NR barrel length rule applied, would a ported .223 barrel beyond 14.5 inches or a ported 300 or 8.6 Blackout with an even shorter rifled portion be useful, presumably with a permanently mounted flash hider be useful for a well-balanced firearm, or would the lack of the ability to change muzzle device be too big a negative?
It doesn't make a lot of sense to me to shorten the rifled portion of a 5.56mm/.223 cal Barrel when you consider that those rounds benefit (velocity, fulll powder-burn) from rifled Barrel lengths up to 20" (eg. M16A1). The reason that SAI only rifles 11" of 9mm Barrel is because full 9mm stabilization and powder-burn occur at roughly 11" and any rifled length longer than that is counter-productive in terms of friction-reduced velocity, barrel harmonics, etc. Much like 9mm, .300 Blk would also benefit from a shorter, 9" portion of rifled Barrel., with the remainder "hogged out" in a manner similar to the R9 Barrel.

Botttom line? Whether a caliber selection would benefit from a shorter rifled portion of Barrel depends on the specific characteristics of the round in question.
 
It doesn't make a lot of sense to me to shorten the rifled portion of a 5.56mm/.223 cal Barrel when you consider that those rounds benefit (velocity, fulll powder-burn) from rifled Barrel lengths up to 20" (eg. M16A1). The reason that SAI only rifles 11" of 9mm Barrel is because full 9mm stabilization and powder-burn occur at roughly 11" and any rifled length longer than that is counter-productive in terms of friction-reduced velocity, barrel harmonics, etc. Much like 9mm, .300 Blk would also benefit from a shorter, 9" portion of rifled Barrel., with the remainder "hogged out" in a manner similar to the R9 Barrel.

Botttom line? Whether a caliber selection would benefit from a shorter rifled portion of Barrel depends on the specific characteristics of the round in question.
Thanks! So in the future, if barrel length is still an NR requirement, but we get back our semi-autos, a ported barrel .300 Blackout R18 MK3 or ATRS Sporter, or even standard AR-15 should those un-verbotened, may make sense.
 
Thanks! So in the future, if barrel length is still an NR requirement, but we get back our semi-autos, a ported barrel .300 Blackout R18 MK3 or ATRS Sporter, or even standard AR-15 should those un-verbotened, may make sense.
Why are you so hell bent on having an 18.6" barrel that only has a functional 11" length? It doesn't hurt anything in 9mm because it doesn't gain anything significant with the extra length, but all rifle calibres should use appropriate length barrels to maximize performance. I'd much rather have an 18.6" barrel with a conventional muzzle device if I can't run a can on it. If suppressors were legal, then a short barrel makes much more sense but hell hasn't frozen over yet, so that seems exceedingly unlikely in this commie land.

I find the R9 barrel ridiculous. I can't run the muzzle device of my choice on it and it's still as long and awkward as every other 18.6" barrel out there. It is lighter, which is a bonus but it's not a huge improvement over a standard 9mm pencil barrel profile.

Mark
 
I find the R9 barrel ridiculous. I can't run the muzzle device of my choice on it and it's still as long and awkward as every other 18.6" barrel out there.
What muzzle device would you run on an 18" 9mm?

The R9 barrel does greatly reduce the overall weight as well as reduce front end weight. If one has to have an 18" barrel, I actually think the R9 setup is for the best. A muzzle device on a long barrelled 9mmP is basically pointless.
 
Some choices are not worth having or at the least not worth worrying about. 🤷‍♂️
I'm not worrying about it, I just won't buy one as it is.

You made your choice - then don't buy one then ... voila
Yep, that is the end result. I'm sure they will sell mine to someone who doesn't care or likes the barrel set up. That's how capitalism works, there can be something for everyone.


Mark
 
Here is a TFBTV article on the Mec-Gar's metal Glock mags that are used in the latest Staccato pistols. They may meet Sterling's requirements for dependability compared to polymer Glock magazines for the R9, while allowing people to use their stockpile of polymer Glock mags for non-critical situations:
In what world are we living in where we pretend polymer glock mags arent reliable lol
 
Trying to remember, but does the charging handle on the R9 interfere with the Akdas collapsing 1913 stock?
The R9 charge handle stores pretty far forward.


In what world are we living in where we pretend polymer glock mags arent reliable lol
Apparently PCCs beat up polymer mags. Glock mags in a Glock are obviously fine. Glock mags in a completely different gun, they were never designed for, is apparently the problem.
 
Trying to remember, but does the charging handle on the R9 interfere with the Akdas collapsing 1913 stock?

The AKDAS Collapsing Stock's Struts will interfere with the Left side Charging Handle (CH) Tracks machined into the Upper Receiver when the Stock is collapsed with its Struts in line with the CH. If the Buttstock is mounted lower, then the Struts should clear the CH altogether, however this would make the Stock's mounting surface quite low on the rear Picatinny Rail.

I tried to fit an original SIG Collapsing MPX Buttstock onto the R9 but found that the R9 upper Receiver is too wide to fit between the Buttstock's Struts. You can still see in the photo where the Buttstock Struts and the Upper Receiver's CH Track will interfere with one another when the Stock is mounted in line with the firearm and collapsed. Clearly AKDAS manufactures a collapsing Buttstock with a wider stance to fit the R9 and R18 (whatever they're named by AKDAS) Upper Receivers, which are the same width. It is unlikely however, that the AKDAS Stocks are sufficiently wide to fit an R9 (or R18, for that matter) due to the presence of the CH Tracks which are not found on the slick-sided Turkish Upper Receivers. As a result, the Turkish Upper Receivers are slimmer in profile than the Canadian variant and can accept the Collapsing Buttstock at any height on the Rear Picatinny Rail.

Bottom Line? Collapsing Buttstocks that employ struts running alongside the Upper Receiver of the firearm will not work on the R9 due to interference with the CH Track machined into the Receiver's Left side. It is possible to mount such a stock when fully extended, however the stock will not fully collapse due to interference with the CH Track.

As an aside, it is interesting to read the comments below the Classic Firearms Video about the "Turkish MCX". Most of the US viewers commented that they would prefer Left-Side Charging over the Turkish version's Top-Charging design. Canadians on the other hand, have commented that they would prefer the Top-Charging system. It just goes to show you that some folks simply, automatically want what they cannot have!


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In what world are we living in where we pretend polymer glock mags arent reliable lol
They weren't reliable for the developer of the R9 to make a Glock version, in his opinion. Thought having metal glock mags froma quality company at reasonable prices may change his mind.

Would a magwell adapter for the current R9 to Glock be possible, or would it have to be a custom lower and/or upper?
 
They weren't reliable for the developer of the R9 to make a Glock version, in his opinion. Thought having metal glock mags froma quality company at reasonable prices may change his mind.

Would a magwell adapter for the current R9 to Glock be possible, or would it have to be a custom lower and/or upper?

It would require a complete rework of the Magazine Well on the Lower Receiver, as it is currently optimized for a straight-up insertion based on HK MP5 Magazines. Glock Magazines obviously require a slanted Magazine Well to accommodate the angle at which they feed. Totally different, including the location and design of a Magazine Catch specific to Glock Magazines.
 
It would require a complete rework of the Magazine Well on the Lower Receiver, as it is currently optimized for a straight-up insertion based on HK MP5 Magazines. Glock Magazines obviously require a slanted Magazine Well to accommodate the angle at which they feed. Totally different, including the location and design of a Magazine Catch specific to Glock Magazines.
Thanks! I wonder if Akdas might already have a lower designed for their variant, since the Glock mag us the defacto standard for the American market. Again, up to JD and Sterling if they want to make a Glock lower to work with metal Glock mags. Depends on the future political climate and customer demand. The Wheel Weaves as the Wheel Wills.
 
Glock mag PCCs look like azz.
I agree the straight down angle of the MP5 mags has better aesthetics. So if no one likes the aesthetics, and no one wants to use Glock mags in an R9 at all, then there will be no demand, and it will not happen. I remember some people complaining about no Glock mags as an option before the R9 came out, but if the majority are happy with it as is, then Sterling has no reason to make a Glock version.
 
I agree the straight down angle of the MP5 mags has better aesthetics. So if no one likes the aesthetics, and no one wants to use Glock mags in an R9 at all, then there will be no demand, and it will not happen. I remember some people complaining about no Glock mags as an option before the R9 came out, but if the majority are happy with it as is, then Sterling has no reason to make a Glock version.
Once you add the Sig MCX folding/ collapsible stock, the aesthetics only increase. The rifle looks good with the double feed MP5 mags.
 
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