It would be good on a 9mm upper. Bolt doesn't need to recoil as far.
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It would be good on a 9mm upper. Bolt doesn't need to recoil as far.
Tube was pretty soft too. I'd use it for a stock mount on a dedicated .22, but little else.
I stuck a 1 inch wide ruler that barely fit down the hole where the spring/buffer go. When it wouldn't go in further I masured to the area where the buffer retainer pin notch is located. At least that is what I remember. The difference between the long and short areas isn't much, maybe 3/32 inch, especially compared to the 15/16 (+) difference between the ArmaLite and Tapco stocks.Quote:
Originally Posted by FireMoth
Cool, i'll give it a measure. I also found that the 'spoon' (my own term for the extension that retains the buffer retainer) is a pretty widely varying appendage. so i'll have to take that into account.
I measured mine from the inside bottom to the retainer lip, using the 1"tape measure like above and the one we pulled off is exactly 6 13/16"
More of a question for FireMoth; what extensions would you recommend and are there any you would stay away from? They seem like fairly straight forward choices, either mil-spec or commercial, but like most things, not everything is equal.
That's a tough one.
I prefer mil spec because in my experience the more square rib at the bottom results in less stock wobble, they are a little shorter, and a little lighter. I also feel that the larger threads (not a different thread dimension, just a larger tolerance .185" v. .170") gives a stronger mount and holds single point adapters better.
However, Commercial function the same from a cycling stand point, so its not like its a huge deal.
I would stay away from anything that isn't properly hard anodized. The cheapy ones tend to look spray painted, and some actually are.
Sadly, most of the time an offending part shows up on my bench, its of an unknown origin, so i cant damn any one manufacturer. I might hazard that Hesse/Vulcan/Blackthorn might have something do do with it, but that's speculation based on their other products.
To play safe, just use known name manufacturers. Doesn't matter if they are regarded as high speed by the 'list'. If they are known enough to be on the list, they are probably ok.
Inexpensive parts like those from DPMS and Bushmaster work fine.
Other than mil spec vs. commercial, there are differences in both that might or might not matter.
There ARE flat backed commercial receiver extensions.
Its diameter is what makes the difference, so that's what you should use to judge. Mil spec is 1.148", commercial is 1.168" on average. There are some minor dimensional differences in each type, so a couple thousandths wont be enough to fuss over,a s long as the stock slides
Another common difference is locking positions. A true Mil Spec M4 stock has only 4 positions. One fully collapsed, and three at the back end. Ther are commercial extensions with this configuration as well.
More commonly, we find a six position stock. Using the same spacing as the last 3 holes on the M4 extension, they simply fill in with 2 more positions close tot he front. This is common to both mil spec and commercial diameter extensions.
Finally, we have the 5 position stocks, such as DD and Vltor. These just have a larger spacing.
All 3 work.
I wish i had a comprehensive list of offenders, but the best i can say is if no one knows where it comes from, its probably not worth the risk.
Thanks for the information FireMoth.
I just finished putting together a lower and will probably be picking up a stock for it in the next few weeks. Based on your reputation and a recent visit to Bowers, I believe I know where I will be picking up the receiver extension and stock.
Maybe you could take a look at it to make sure it won't short cycle on me. [Flower]
Good information Rob! I wish the one that I had issues with had a name on it so we could steer clear of this model.
I think the best advice you gave was; "the best i can say is if no one knows where it comes from, its probably not worth the risk."