Firing Pin Retaining Pin ?

[REARSPROCKET]

Haven't seen this discussed here, seems the AR10 and the 308AR BCG take a (larger?) specific firing pin retaining pin. I have seen both the original AR style solid pin with a split on the end used and the newer cotter pin style. Where is the best place to source the cotter pin style FP retainers ? 

[98Z5V]

Yes, they do use larger, longer pins, if you're comparing it to the AR15 part.  No way, no how will the AR15 part work in a .308AR. 

Searching online is the best way, just to find some - but everything is backordered right now.  I'm on a waiting list for 4 of the solid pins, just waiting.  Used my last spare a few weeks ago.

[edgecrusher]

I may have one, need to check parts bin tomorrow after work

[REARSPROCKET]

The Aero carrier I have came with the solid pin, but when installed the tip with the split end sticks out the side of the carrier too far and will contact the upper. So I need a shorter solid pin or a cotter pin style .

[392heminut]

5 hours ago, REARSPROCKET said:

 So I need a shorter solid pin or a cotter pin style .

Or a file and just a little bit of elbow grease!

[98Z5V]

Yep, cut it down.  Pics would help, so we could see how much protrusion you're talking about.  Pics of actual problems are becoming rare these days, it seems. 

[REARSPROCKET]

So I ordered some S&W M+P10 retainers and they arrived today, it seems S&W uses the smaller 5.56 FP retainers in their 308 platform?. The original FP retainer's split end sticks out about 3/32 - 1/8  past flush. If I shorten the tip the chamfered nose of the split will be gone. I measured the diameter of the solid pin at .123 so it seems they are 1/8". I forgot to measure the length to see if there is a shorter cotter pin style I can modify to use. 

[REARSPROCKET]

I measured with caliper it sticks out .045 and the OAL length of the solid pin is .945 so I guess I need a .900 length pin. Could someone measure the length of their pin so I know if this one is out of spec ?

[392heminut]

My spare retainer pin measures at .880 so my guess is that you have an out of spec retainer pin.

[REARSPROCKET]

Thanks I'm glad it's not the carrier. 

[REARSPROCKET]

Hemi would you know what brand or who the manufacturer is ? Seems there are other pins out there that are the same length as mine.

[392heminut]

2 hours ago, REARSPROCKET said:

Hemi would you know what brand or who the manufacturer is ? Seems there are other pins out there that are the same length as mine.

Sorry, I've had this thing in my spare parts for a couple of years now and I don't remember where I got it. Hell, I wake up in a whole new world every morning, old age will do that to you!

Edited January 29, 2021 by 392heminut

[392heminut]

I'm pretty sure it was this one, which is discontinued new since DPMS was sold.

https://www.midwayusa.com/product/1003343920

Yup, just checked back through my orders there and that is where I got it back about 4 years ago.

Edited January 29, 2021 by 392heminut

[DNP]

Who was the guy on here that was putting together the spare parts kits?  Was that dwilson?  Anyone remember?

[shooterrex]

KNS is who makes the retaining pins I use. Solid w/split ends.

https://www.joeboboutfitters.com/KNS-Perma-Pin-Firing-Pin-Retainer-p/kns-perma.htm

That is the one for the AR15 but they also make them for the large frame guns.

[98Z5V]

7 hours ago, DNP said:

Who was the guy on here that was putting together the spare parts kits?  Was that dwilson?  Anyone remember?

Yep, that's who it was. 

[jtallen83]

16 hours ago, DNP said:

dwilson

A few parts but no BCG parts;

http://www.dwilsonmfg.com/Parts_c_18.html?viewall=1

[REARSPROCKET]

Thanks, I looked up the KNS pins and they are not available for the 308 only 5.56 on their site ? I was thinking maybe a small o-ring under the head side of the pin would keep it centered and not protruding ? 

[392heminut]

Seriously, just file the thing down! Even if it doesn't leave that much of the split portion, once it's in the upper the pin can't go anywhere!

[shooterrex]

KAK not KNS sorry

https://www.kakindustry.com/kak-bcg-firing-pin-retainer-308

[REARSPROCKET]

Thanks guys, I ordered a few different pins from KAK, RCA and some regular cotter pin style, so I'll see what shakes out with them when they get here. I noticed Toolcraft uses the cotter pin style in their 308 carriers so that might be the best way to go. 

[98Z5V]

5 hours ago, REARSPROCKET said:

 I noticed Toolcraft uses the cotter pin style in their 308 carriers so that might be the best way to go. 

I bent one, and so did a buddy.   We're not exactly running factory ammo, either.  That's why I switched everything over to the solid pins.  The cotter pins are spares in the box, in case I break a solid pin, and am waiting for another to come in.

[mrmackc]

On 1/30/2021 at 6:32 PM, shooterrex said:

KAK not KNS sorry

https://www.kakindustry.com/kak-bcg-firing-pin-retainer-308

Thanks, I ordered three of them.

[98Z5V]

I hope they send me my cut, like they promised...  

[shooterrex]

57 minutes ago, 98Z5V said:

I hope they send me my cut, like they promised...  

How does that work? I posted the link and you get a cut?

Sat down w/Dave last night and discussed what he needs to order for his 6ARC.