Recoil buffer pad material

[jliston48]

Has anyone experimented with different materials to use as replacement recoil buffer pads in semi-auto pistols? My specific enquiry is about the Domino/FAS SP602 (22LR) and the FAS CF603 (32 S&W Long). I notice that the 22/32 Sako 3-in-1 has a buffer also. Possibly other pistols also have them too.
The originals look like a medium/high density translucent polymer. I am wondering whether compressed rubber matting would work as a replacement.
I bought some original replacements a few years ago and when I went to check them, they have started to disintegrate (crumble).

[Leon]

There was a post a couple of years ago by a FAS owner in Qld who was successfully making his own buffers from poly something or other. A white looking material.

Interesting to note that replacement Benelli recoil buffers I've just received from Larrys Guns in Maine are made from the same material - reputed to be more durable than the factory originals.

[BobGee]

Bit of a late reply but a well recognised but ancient shooter/gunsmith with considerable knowledge of Margolins recommended either a leather buffer or one made of a kind of plastic by the name of luretine/lurethane(?), both of which are "dead" unlike the rubber sheep castration rings used by some.
I made some for my Margolins out of an old leather belt of my wife's and they work well. Might be useful in other pistols too.

[jliston48]

Thanks Leon & BobGee.

I haven't yet found the old post but I will look again - the situation is now desperate!

Necessity is definitely the mother of invention.

Last weekend at an open shoot I decided to give the FAS CF603 a big clean before my Centre Fire match - not just the chamber and slide clean it usually gets. When I did, the recoil buffer fell out like powder. (I hadn't checked it for some time - obviously).

What to do at 9:00pm on a Friday night? An old silicon rubber mosquito repellent wrist band came to light in my travel bag. It was stretchy and soft, maybe too much so. Idea #2 - Elastoplast tape about 10mm wide in the First Aid kit. I experimented by winding a rectangular wad of this stuff to about 3mm thick. Looked good - not too elastic and had a reasonable shock absorbent effect. Tried it and if felt good for a temporary fix.

The buffer retaining clip arms were a bit loose in the holes so squeezed them a bit to give them some grip and "SNAP" - one of the arms broke off. Crap! They were hardened steel - who would have thought...? So assembled the recoil assembly with a toothpick jammed in the hole to secure the recoil buffer plate with the good arm.

I thought that if I get through the precision stage with no problems, I would not touch it before shooting the rapid fire stage. The gods were smiling on me - no problems at all - just a lousy score.

Now I need to do some repairs before training this week so parts are a priority

PS - Note for diary: CLEAN PISTOLS THOROUGHLY, REGULARLY!

[Leon]

You can use either polyurethne or polyethylene - obtainable in sheets from here -

http://allplastics-px.rtrk.com.au/produ ... product/24

[Fortitudo Dei]

I've noticed that FAS seems to have changed the material they use for their buffer pads. The older type was coloured red and these would age and crumble very quickly. The last pair of FAS603 buffer pads I purchased from Potters were made of a light-green material and these have been much more durable (by several orders of magnitude. I'm still on my first green pad and after a year it is still in excellent condition).
Note that certain types of gun cleaner can turn recoil pad material into slimey mush, so do your best to keep these away from them when cleaning and oiling your gun.

[JamesH]

Polyethylene is completely unsuitable as a buffer, polyurethane can be OK - there are many different hardnesses and hysteresis levels available.

[jliston48]

I have decided to buy the genuine replacements from Potter Firearms (Aus importers) and save all the trouble of experimenting - particularly if they have changed materials from the amber-red "stuff" that disintegrates.

If I continue to have problems, I will have to have a talk with the people at Allplastics or Dotmar (http://www.dotmar.com.au ), both of whom are specialists in the supply of a range of polymeric materials.

[jliston48]

I bought the replacements from Potters Firearms and they have worked well. They are a hard black rubber and not like the original material.

Next time, if I made my own, I would start with a high density "tyre" type compound - or rubber floor mat-type material about 3mm thick. That seems to be what the replacements I bought look and feel like. The material would have to be unaffected by all types of oil and grease (which I don't think the originals were and that is why they broke apart - but they had been in the pistols for many years too!)

[Gwhite]

The Pardini SP buffers are cast from a fairly stiff green rubber. The rubber gets harder with age, but I've never seen one disintegrate. The rubber is VERY tough. One buffer had a small bit of "flashing" from the molding process. Even using a surgical scalpel, I had difficulty trimming it off. Because of the shape, I think it would be very difficult to make a suitable replacement. I think it might be a high strength silicone rubber of some sort. I suppose if you could get it in a squeeze tube, you could make a mold & try to cast your own. You can also get castable urethane, which is available in several hardnesses.

[SamEEE]

Delrin has some good properties.

I know they make 10/22 pin buffers out of the stuff.

http://www.sdplastics.com/delrin/delrin%5B1%5D.pdf

http://www.dupont.com/products-and-serv ... resin.html

https://en.wikipedia.org/wiki/Polyoxymethylene

So assembled the recoil assembly with a toothpick jammed in the hole to secure the recoil buffer plate with the good arm.

*Approving nod*

[j-team]

Acetal (Delrin) might be a bit hard (although it's really nice to machine).

I would be inclined to use Urethane. It's a pain to machine (grinding is the best approach) but will have good effect as a buffer, and will take a beating. It comes in different grades which are usually colour coded but don't ask me to remember which is which!

[Anders Turebrand]

I have looked at buffers in several pistol designs and most (all that I have seen...) seem to be square and they also fill out the space they occupy, meaning that there is no space for movement in the buffer.
For me, the proper design would allow for the buffer material to be displaced, like industrial buffers shaped like a round nosed bullet.
However I believe most such designs simply will not fit in the pistols because they would necessarily be longer than the original designs...

[JamesH]

I wouldn't use Delrin/POM

In order of choice I'd go with urethane, rubber, leather, I'd start off with ~Shore 60-70 A.
Dotmar have a wide range of urethane in different hardnesses and thicknesses off the shelf.

Some idea of hardness values.