A registered business in the state of Colorado (ID# 20091276671 / 20131415285)
HBA Cause 4 K9s is a registered non-profit in the state of Colorado (ID# 20131451644)

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Suomi M31 80% Receiver AND Lower Siderails - Reduced ID
Suomi M31 80% Receiver AND Lower Siderails - Reduced ID Quantity in Basket: None
Code: M31RID
Price: $215.00
Shipping Weight: 1.00 pounds
Receiver comes with Template installed.(Front stubs come uninstalled to allow cutting out of Mag Well).
Tube comes threaded for the rear cap, front shroud lugs are cnc cut and the ejector is installed
Remaining tube work to be done includes, opening of magwell, ejection port and triming of the front stub to fit the barrel (key or Keys if using the Tommer Design)
Tube lowers require final shaping and drilling of pin holes along with welding of the lowers and the filler stub to the finished tube

Please note:
The lugs for the shroud to lock "on to" are machined and then hand fitted tight here at the shop - this is done so that weather your shroud is brand new/over size in spec and tight or worn/under spec and loose you can finish the lugs to fit your particular shroud. Yes - this means most people will need to remove a slight bit of material by hand from the rear of the lugs to get their individual shrouds to "lock" in place however this also means MOST ALL shrouds can be fitted very well to our tubes where as a "One size fits all" approach would be tight for some and loose for others. I understand that some people may see this as a inconvenience but with the provided reasoning I do hope it can be seen as a benefit by most.

The same logic was applied to the barrel socket - it is intentionally about .006 undersized - this means most will need to do some light sanding in the socket (or barrel shaft) but it also insures a good tight fit when the build is done. To ream the socket to fit most/all barrels would mean it would fit many barrels poorly.

It is a small amount of work to be done but both instances will lead to a much better firearm once it is built.

As these are built to order, we ask that you allow 4 to 8 business weeks from receipt of payment for shipping to occur.

All ATF/NFA rules apply to purchases made from this site.

 The information/products in these web pages are not intended to be used to construct illegal firearms.

 It is the sole responsibility of the purchaser to know and understand all applicable Federal, State and local laws before placing an order.
By placing any order you are agreeing that you accept all legal responsibility for the products purchased and their subsequent use.

For legal semi auto and dummy gun information, contact BATF at: www.atf.gov

Every reasonable effort has been made to ensure that all photographs, descriptions and specifications on this website are accurate.
However, inadvertent errors may occur, and changes in design or materials, due to our continual effort to improve products, may result in some change in specifications before subsequent publications are issued.
HBA reserves the right to modify or change specifications with or without notice at any given time.