finding someone to machine custom parts?

[jason41987]

hey everyone, i have a future AK project in mind, and im wondering if anyone knows a place where i could have a couple custom parts machined for it?...

parts will include a custom front trunnion, with a raised section to hold the top cover and gas tube, no sight, and will allow the barrel to be free floated

a front gas block that will include a top rail for a flip up front sight

and a receiver-end barrel extension that will contain the locking lugs of the AK, and be threaded to accept aftermarket threaded barrel blanks

the top cover will be hinged in the front, and the top cover will have block inside it that will fall inside the rear trunnion and be pinned with a captive pin like an AR15 has, or have a cammed shaft with a lever for opening the top cover, so the rail will maintain zero and a flip-up rear can be mounted

anyone know anyone that can do this kind of work, and what costs they may charge?... trying to determine if its better to outsource for these pieces for a personal rifle of my own, or buy the machine to do it myself (i had plans of rebuilding an old bridgeport and converting it to CNC)

 

[Jim K]

I assume you are building a rifle for your own use and are not a licensed manufacturer.

If so, there could be a legal problem since BATFE has said that if a person wants to build a firearm (receiver) for his own use, he cannot have the work done by anyone else unless that person is a licensed manufacturer.

I suggest writing BATFE before proceeding to farm out that work.

If things are OK on the legal front, any machine shop should be able to make what you want. Call around and find one that is "gun friendly" and will understand what you want. You should also have good drawings, with correct dimensions, including thread pitch of the barrel hole. You don't need full engineering drawings, but you need something they can work from. But be sure to leave some leeway; better to have to do a bit of filing than to find out the part made to your measurement is too small.

Jim

 

[Sam1911]

He didn't say he was wanting them to make the firearm (receiver), just a bunch of non-regulated parts.

If that wasn't legal, it wouldn't be legal to build an AK on a flat you bent yourself, as all those same parts would come from a parts kit made in a factory in Russia, Bulgaria, Romania or wheverever. The "builder" is just making the receiver shell, and that's perfectly legal.

 

[jason41987]

i dont do technical drawings or blueprints anymore... just 3D solid model/3d cad which is much better... i could draw out what i need in solidworks or inventor and submit that to a few places, any idea what something like these parts could cost?

basically for the trunnion, to best describe this is anyone familiar with the front end on the valmet AKs?... i believe theyre milled, but the trunnion design would give you a valmet like front end on a stamped AK.. purpose of this is to both lighten up the rifle, as well as free float that barrel by getting that massive metal block off of the barrel (the rear sight block) as the hinged top cover with a lever to lock it in the back will maintain a perfect zero allowing a rear sight mounted to the receiver

the barrel extension will be to make barrel changes tool-less. itll be for myself, not selling it as a rifle.. however, if i did intend on manufacturing something like this to sell, it could be sold as a parts kit intended to be installed on an AKM receiver supplying a front trunnion, rear trunnion, barrel, and top cover, all the rest would be standard AKM parts

 

[45_auto]

You're probably looking at a minumum of a day for each part to do set-up and machining. Figure 8 hours each at $60-$80 per hour minimum depending on where you're at. You're somewhere in the neighborhood of $500 each. Are AK trunnions heat treated? It'll need to be sent out for heat treat if so, don't forget to add that in.

Are all your tolerances in the 3D models? For instance, is the trunnion 2 inches plus or minus .0001" long, 2 inches plus or minus .030" long, or 2 inches plus or minus .010" long? That will make a huge difference in price. I know it's EXACTLY 2 inches long in the computer model, but it's not going to be in real life. You'll need that for every dimension, hole, and hole location in the model. We find it much faster to quote off a drawing rather than have someone open a model and have to go through every single dimension in it looking for specific tolerances. You'll find that very few places (none that I know of) will quote off a bare solid model.

 

[jmorris]

If you only want one of anything most machine shops won't want to bother with you. Some will get you on the hook with $80/hr figure and you'll seldom get anything that works back. Generally the shops that can turn out quality parts that are not already available don't give quotes but estimates.

Once you go "outside the box" prices go way up.