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View Full Version : Building vs. buying an upper?



jvencius
26 August 2008, 05:52
I'm trying to plan what to do for an upper to go on the Frankenlower I have in the closet and have a few questions that, if you don't mind answering them, would help me plan some more. I'd like a 16" pipe (so I can fiddle around with flash suppressors before having it chopped/pinned/welded), 1:7, 4150 steel, M4 contour/cuts, standard FSB, flattop so here are my questions:

1) Since I already have the tools (vise block, AR multi-tool, punches, etc...), is there much, or any, cost advantage to building an upper vs. buying one assembled? I'm not looking at a rare/unique upper combo so it's not as if I want something that just isn't built in any factory.

2) I'm fairly handy and enjoy tinkering/mechanical bits so given that, is building an upper really all that hard (I've done a lower already) or is it pretty easy so long as you take your time?

3) Headspacing--how does one ensure a separate barrel/bolt/upper combo headspace properly? I don't have a set of Go/NoGo gauges yet but will get them before I would think of assembling an upper--they'll be on my next Brownell's order.

4) If I get an upper w/o M4 feedramp cuts, is it OK to Dremel the ramps open or would that jack up the anodizing hardcoat?

5) Are there any books/DVD's you would recommend getting to have on hand before I start on this project (if I build an upper at all)?

TigerStripe
26 August 2008, 14:36
My answer is at the Armory. I'm sure you'll get more expert opinions than mine here.



TS

Dutch
26 August 2008, 20:46
I'm trying to plan what to do for an upper to go on the Frankenlower I have in the closet and have a few questions that, if you don't mind answering them, would help me plan some more. I'd like a 16" pipe (so I can fiddle around with flash suppressors before having it chopped/pinned/welded), 1:7, 4150 steel, M4 contour/cuts, standard FSB, flattop so here are my questions:

1) Since I already have the tools (vise block, AR multi-tool, punches, etc...), is there much, or any, cost advantage to building an upper vs. buying one assembled? I'm not looking at a rare/unique upper combo so it's not as if I want something that just isn't built in any factory.

Well if you have already assembled a lower receiver then I would believe you have the skill ability and patience needed to assemble an upper. Putting it together yourself give you the same advantages as building your lower. Your schedule as far as available funds, the chance to shop around a bit for prices or sales, and getting what you want without having to immediatley modify it to your desire

2) I'm fairly handy and enjoy tinkering/mechanical bits so given that, is building an upper really all that hard (I've done a lower already) or is it pretty easy so long as you take your time?

You should have no problems putting it together as long as you take you time and pay attention to what your doing. Also don't over or under torque the barrel

3) Headspacing--how does one ensure a separate barrel/bolt/upper combo headspace properly? I don't have a set of Go/NoGo gauges yet but will get them before I would think of assembling an upper--they'll be on my next Brownell's order.

If you were to get the barrel and bolt from the same manufacture you shouldn't have problems with head spacing. Normally head spacing is rather important to watch if an when you start mixing and matching parts with different life histories (i.e. new barrel to older bolt) or from completely different manufacturers. The idea there is if one company measures to the .001 or .0001 those things can add up to cause issues

4) If I get an upper w/o M4 feedramp cuts, is it OK to Dremel the ramps open or would that jack up the anodizing hardcoat?

I haven't done it before but i would assume you would "jack up" the anodizing as you are cutting away material


5) Are there any books/DVD's you would recommend getting to have on hand before I start on this project (if I build an upper at all)?

TM16A2 / M4 / M4A1 Technical Manual M 9-1005-319-23&P

Dutch

Stickman
26 August 2008, 21:17
I've hacked up an upper to put in M4 feedramps, and yes, you cut away the hardened surface of the anodizing. Its worth getting the right parts the first time.

SHIHAN
27 August 2008, 14:42
I've hacked up an upper to put in M4 feedramps, and yes, you cut away the hardened surface of the anodizing. Its worth getting the right parts the first time.

In a big Kool Aid Man voice OOOOOOHHHH YEAH!

John Hwang
27 August 2008, 21:38
For proper head spacing, you will need a Go & NO Go gauges. You can run an upper without M4 feed ramps with a barrel with M4 cuts without issue. You can dremel in the feed ramps but why?? They will work fine without them.

jvencius
30 August 2008, 12:44
The more I try to calculate parts costs, the more I figure buying an upper pre-built (and has something of a warranty) makes sense. Based on cost alone, for the parts I'm looking at I'd be out ~ $700 for the uppper (the Vltor CASV-EL is 1/3 of that) and I can buy an upper already assembled for the same money. I have most of the tools, so the sunk cost for them really isn't a concern, but it would be nice to open a box, pin the upper on my assembled lower, and head to the range vs. having to spend who-knows-how-much time fiddling with assembly when I'm not positive what I'm doing.