What are "anti-walk pins?"

dolfan

A Colt SP-1 on auction is described by the seller as "has anti-walk pins installed by previous owner who shot at DCM competitions."

What are these pins and can they be removed?

Thanks.

tsavo303

he is reffering to pins that are not just friction based(have a E clip or something to secure). He maybe confused with the large whole front on the colt SP_1s that are bolts.
Either way, colt sp-1s are great! I was just thinking today what a great gun that is[:D]

drsck

"Anti-walk pins" is a reference to the type of pin holding the top and bottom parts of an AR together. The standard pins allow for some wiggle that can result in the point of impact "walking" on the target. The "anti-walk pins" are tighter and therefore keep the upper in lower in tighter configuration and eliminate the wiggle resulting in greater accuracy. Yes, they can be removed and replaced, but apart from the slight inconvenience of the upper and lower being somewhat more difficult to separate, there really isn't any reason to replace them. A set from Brownell's will cost about $10.00 and the cheaper standard pins will run about $4.00. Best of luck -- Steve

dolfan

Thanks guys for the info.

cpermd

The above answers are wrong or I am interpreting them incorrectly.
Antiwalk pins are for the hammer and trigger pins on M16s.They keep the pins from walking out the side of the lower receiver under FA fire. I have heard it is usually the hammer pin that walks out, but I have never seen it.
Some people use them on ARs.
They protrude a bit and have a C clip.
Has nothing to do with the upper and lower receiver fit.

Let me know if I am wrong.

CP

Txs

cpermd is correct.

I've seen failures from this during extended SA range sessions, not just with full-auto.

Laredo Lefty

CP is correct....

The anti-walk pins people refer to are the hammer and trigger pins, not the front & rear reciever pins.

Normally internal springs keep these pins from "walking". The "C" clips are an added measure. Actually they can walk in semi or full-auto fire.

On a couple of my AR's I've noticed that the hammer pin does not walk sideways but rotates with the hammer instead of the hammer rotating on the pin. This will accelerate wear on the reciever holes when the pins rotate in the hole.

The below gun is my Lt hand AR. Notice the little bridge running between the hammer and trigger pins. These are available from Brownells and lock the pins from rotating so the hammer rotates on the pin and the pin stays put in the reciever hole.

[img][/img]

BHAVIN

cpermd is correct. They are for the trigger group.

givette

+1 on cpermd's explaination. The C-clips are designed to prevent lateral pin movement (walking). Lefty's setup [Brownell's] prevents both lateral and rotational movement to the pins. Best, Joe

4440rk

+ on the hammer and trigger pins. Check out KNS Precision for their latest style.

CobrayKid

I thought they were like the pins on the AK, where theres a slot in them to keep them from coming out (which it did, once cause I didnt put the shepards hook in right)

Txs

quote:Originally posted by CobrayKid
I thought they were like the pins on the AK, where theres a slot in them to keep them from coming outThey are, only they're retained by E-clips instead of utilizing springs already in the gun's internals.

Lefty's pic shows anti-walk pins which are also connected to prevent pin rotation. This anti-rotation connector is what you're seeing on the outside of his receiver.