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Re: AIA 7.62x39 cast boolit build
Posted: Mon Nov 24, 2014 11:42 am
by Alpha1
I never thought of that it would probably fit through my spindle bore. The barrel is tapered though.
The down side is I have never done any thing like that before I'm not sure I could manage it my self.
Re: AIA 7.62x39 cast boolit build
Posted: Mon Nov 24, 2014 12:00 pm
by ovenpaa
Well you need to support the barrel at both ends of the spindle, I use a spider for both ends however you can use a 4 jaw for the muzzle end and a very simple spider for the outboard end and then just clock both ends in, remember you should be clocking the bore as opposed to the barrel outer diameter. You can crown it to a variety of profiles, a short boring bar and compound slide set to 11 degrees is a rough and ready way however it can give good results, work from the bore outwards.
Re: AIA 7.62x39 cast boolit build
Posted: Mon Nov 24, 2014 11:24 pm
by Alpha1
Well you need to support the barrel at both ends of the spindle, I use a spider for both ends however you can use a 4 jaw for the muzzle end and a very simple spider for the outboard end and then just clock both ends in, remember you should be clocking the bore as opposed to the barrel outer diameter. You can crown it to a variety of profiles, a short boring bar and compound slide set to 11 degrees is a rough and ready way however it can give good results, work from the bore outwards.
I understand what you are saying about supporting the barrel. When you say you use a very simple spider for the outboard end could you elaborate please. I don't understand how the spider is supported on the out board end if the muzzle is in a four jaw. Thanks for your patience by the way and your tolerance of my stupid questions their are some people on here who should take lessons from you.
I spoke to Allan at work to day about re crowning the barrel He offered to do it for me. I'm not sure if that's allowed with it being a firearm. Id love to have a go but I need to understand the process.
Re: AIA 7.62x39 cast boolit build
Posted: Mon Nov 24, 2014 11:54 pm
by Blu
Hey troll, seriously old son if you aren't sure how to do it then learn how to do it first. I've re-crowned a couple of barrels in the past, the best way to learn is to watch someone else do it first. A good wee tip is to film the process as well, get whoever does it to explain what they are doing as they do it, that way if you attempt it yourself later on down the line you have a visual to refresh your memory.
Once you've seen it done it's not really difficult but you really have to know what you are doing.
Re: AIA 7.62x39 cast boolit build
Posted: Mon Nov 24, 2014 11:59 pm
by Alpha1
I totally agree with you blu. Allan at work is 67 years old and has spent his life in the machine shop he is amazing to watch. We all work in a research facility the stuff he produces is unreal. He does a lot of work on experimental materials. I would love to give the AIA to him and watch him do it. But as you know its not that simple in the UK.
Re: AIA 7.62x39 cast boolit build
Posted: Tue Nov 25, 2014 12:13 am
by Blu
Well however which way you get it done observe first, record and try it yourself later. At the same time have a look on Youtube, there are plenty of videos on there on the subject and on how to do it.
Re: AIA 7.62x39 cast boolit build
Posted: Tue Nov 25, 2014 12:37 am
by bradaz11
you're only facing off with a taper? if you know what you are doing with a lathe, it shouldnt be a hard job?
Re: AIA 7.62x39 cast boolit build
Posted: Tue Nov 25, 2014 2:17 am
by Blu
if you know what you are doing with a lathe, it shouldnt be a hard job?
Ah those famous last words that have brought a tear to the eye of many a man

Re: AIA 7.62x39 cast boolit build
Posted: Tue Nov 25, 2014 2:19 am
by bradaz11

, tell me about it! especially when you get it almost perfect, and then think i'll just take one more pass.....
Re: AIA 7.62x39 cast boolit build
Posted: Tue Nov 25, 2014 9:34 am
by ovenpaa
Alpha1 wrote:
I understand what you are saying about supporting the barrel. When you say you use a very simple spider for the outboard end could you elaborate please. I don't understand how the spider is supported on the out board end if the muzzle is in a four jaw. Thanks for your patience by the way and your tolerance of my stupid questions their are some people on here who should take lessons from you.
If you have a section of the spindle sticking out of the end of the lathe you can build a sleeve that clamps to it with four screws at 90 degrees, alternatively you can build a bushing with four screws that pushes into the spindle bore, something like this. I use grub screws to keep things a bit safer and you can bore the noses and set in some brass pads. You can also add a simple O ring to prevent the bushing falling out.
With a spider or 4 jaw on the other end and this simple spider outboard you can safely hold and align a barrelled action until you can build something more permanent and even something as simple as this will give superb accuracy.