Modern Sporter builds Q&A

[Trashblaster]

I've bedded my upper and lower together. But now as the fit is snug the front takedown pin is tight. As my pin doesnt sit proud it's difficult to move the pin. Does anyone have info on which pins sit proud on the left side?

[$kull]

I've bedded my upper and lower together. But now as the fit is snug the front takedown pin is tight. As my pin doesnt sit proud it's difficult to move the pin. Does anyone have info on which pins sit proud on the left side?

Enhanced pins like battle arms will do you well and stick out

[G.Mitchell]

Got a quick question, maybe this has been answered in one of these threads already...

I read about the rear takedown pin not being a milspec part but being a proprietary part. Seems like folks were having ATRS modify the rear takedown hole so it would take a milspec pin.

Is this still the case? Is this mod worthwhile or can spare Sporter specific pins be purchased from ATRS?

[purplezuk]

Atrs was/is doing this modification at a cost to the buyer.
It’s definitely not necessary unless you have a trigger that otherwise may not fit.
I did mine, mostly for aesthetic reasons

You’d never need a spare rear pin as is a steel, non moving part, and is extremely unlikely that you’d ever have an issue with it

[G.Mitchell]

Atrs was/is doing this modification at a cost to the buyer.
It’s definitely not necessary unless you have a trigger that otherwise may not fit.
I did mine, mostly for aesthetic reasons

You’d never need a spare rear pin as is a steel, non moving part, and is extremely unlikely that you’d ever have an issue with it

Thank you. I’ll see if I can find any photos showing the difference.

[XLNC]

Got a quick question, maybe this has been answered in one of these threads already...

I read about the rear takedown pin not being a milspec part but being a proprietary part. Seems like folks were having ATRS modify the rear takedown hole so it would take a milspec pin.

Is this still the case? Is this mod worthwhile or can spare Sporter specific pins be purchased from ATRS?

It's a fixed rear pin as it does not need to be removed to install the upper onto the lower, but the pin/hole size is milspec. The lower receivers do not come drilled for the detent/spring that standard ARs use to hold in the rear take-down pins though, so if you wanted to use a standard AR rear take-down pin you would need ATRS to drill a detent/spring hole for you. You can also use a KNS rear take-down pin, as they work without a detent/spring (they are internal to the pin).

[polkey]

Has anybody had issues inserting metal magazine? It seems my upper has a slight lip that protrudes into the magwell preventing 3 out of my 5 mags from being inserted. Of the 2 will go in only 1 will drop free.

[G.Mitchell]

It's a fixed rear pin as it does not need to be removed to install the upper onto the lower, but the pin/hole size is milspec. The lower receivers do not come drilled for the detent/spring that standard ARs use to hold in the rear take-down pins though, so if you wanted to use a standard AR rear take-down pin you would need ATRS to drill a detent/spring hole for you. You can also use a KNS rear take-down pin, as they work without a detent/spring (they are internal to the pin).

Thanks for the explanation. Guess I’ll leave it alone then.

[G.Mitchell]

I’m reading lots of complaints about mag compatibility. How common an issue is this?

I’d planned to use Gen 3 PMAGS, and the metal 10/30 mags S&J have/had. Maybe the Canadian made pistol mags too.

Is the mag issue something the end user can fix?

[P11]

Has anybody had issues inserting metal magazine? It seems my upper has a slight lip that protrudes into the magwell preventing 3 out of my 5 mags from being inserted. Of the 2 will go in only 1 will drop free.

contact atrs. the upper needs to be fixed.