Shimming a bolt pin

[Spider]

The lurker eigenram instructions say it is a good idea to shim the bolt pin where it fits into the ram slot so that there isn't too much play in the bolt.

This sounds nice, but what can you shim it with that won't fall off into your ram sleeve eventually?

[KeenDean]

Ok, I just downloaded the manual for the Alias ram seeing as I have the Gen4 ram. It quotes;

"Another modification is to shim the bolt pin in the bolt pin catch. In some bolt pin setups you may find more slack than normal in the bolt pin. This can be alleviated by adding to the pin or pin catch a thin shim, and securing it in place with glue. A snug pin fit that is not metal on metal can help tighten things up".

I would first assertain if you need to have the bolt shimmed? Are you experiencing a lot of play/wobble when you fit the pin.

The instructions are a bit confusing. My only recommendation would be to either contact Lurker directly via email lurker27@aol.com and ask for clarrification. Or alternatively if I have interpreted the instructions correctly, I'd try this.

Obtain some very thin plastic card (usually available from hobby stores), and cut a small rectangular piece that fits the profile of the bottom of the bolt pin. Remember, your dealing with fractions of an inch here, so nothing rediculously thick. Use a small amount of strong adhesive, (like superglue) and secure the tiny strip to the pin. Wipe away any excess adhesive with a damp cloth. Allow plenty of time for the glue to set. Smooth/cut away any excess material. Fit the bolt and see if there is any play in the bolt when it is located in the ram location groove. If you have selected a plastic shim that is slightly too thick and the pin wont engage into the ram, gently file a small amount off with a hand file.

It all sounds a bit "trial and error" and other forum tech heads may flame me for this, but I think this is how they recommend rectifing this problem.

[Spider]

Mine has a little more than 1/32" of total play. Which is a little aggravating for two reasons. The first is that it is at least half of the recommended adjustment for the bolt protruding into the breech when setting the adjustable ram cap. The second is that when the eyes can't see the ball on occasion, I can pull the bolt back that much and it works.

I thought about the plastic, but I don't expect it would last very long. I think I will have to try some sheet brass over epoxy. I don't get the 'metal on metal' part of the instructions either. We're starting with stainless on aluminum.

Thanks for the input. I'm just worried about my 'shim' falling off into the ram and chewing it up. That would turn a minor performance issue into a real pita.

[KeenDean]

One other possibility would be to purchase a new bolt pin. It may be an unwanted cost right now, but like you said, weigh up the cost of a new bolt now compared to having to replace a ram tube because the shim worked loose and scored the hell out of the internals.

You could try Buy/Sell/Trade threads in various forums. Or you could buy brand new. I've done a quick search for you and found this at paintball kingdom. http://www.paintballkingdom.com/index.asp?PageAction=VIEWPROD&ProdID=365

Or if you have the time and funds you could try acidcustompaintball in Australia, http://www.acidcustom.com/

Here is the gallery of some of his custom work, VERY NICE. http://smg.photobucket.com/albums/v471/acidcustom/bolt%20pins/

[Spider]

I tried a slightly used shockteck bolt and it fits the same as the old stock bolt. Since the groove in the ram is clean and smooth, I guess it was made a little wide.

I might check out a custom bolt pin though, that has some interesting possibilities.

Honestly though, I owe the whole rig a few more cases of paint before I continue the tweaks.

[Spider]

I checked the dimensions of the pin and the ram slot;

pin width = 0.189 inches
ram slot = 0.220 inches

So it was slightly under 1/32", but that was still a pretty good guess. The shocktech pin and the stock pin were the same width. I probably will try a plastic shim on one of the bolts. For reference, a Lowes gift card is about 0.030 inches and a dress shirt collar stay is about 0.021 inches. Since gift cards are laminated and I need space for epoxy and some slack for fitting, another set of collar stays will bite the dust. :D

[crankwalk]

Good thinking, let us know how that turns out.. if it works i bet there will be a couple paintballers out there with new dress shirts :p