Big Red here with a question from "Ernie Henson"...
So, TAKE FIVE!
“Big Red, my nylon liner doesn't fit well in any of my helmets. Is this normal or do I just have a bad liner?”
Hey Ernie, great to hear form you. Your liner fit issue is common and a known problem. Let me give you a little background and explain...
The Army struggled with the shortcomings of the M-1917 helmet’s liner system for 17 years before the adoption of the Helmet Pad Assembly in 1936.
Similarly, issues arising from the modification of the Riddell Football Helmet suspension system, in 1941, to a “one size fits all” for use with the M-1 helmet was not formally addressed for almost 22 years.
In 1963 the first attempt to address comfort and stability issues with the M-1 helmet occurred with the introduction of a new suspension system. This system had a bar buckle adjustable cradle and attachments for a 3-point neck strap. This new suspension system first appeared in traditional resin impregnated cotton duck cloth liner bodies alongside contracts issued for the development of liners to be constructed from resin impregnated nylon.
The switch to nylon was the first move to a material that would add ballistic resistance to the M-1 helmet assembly. Various contracts, offering differing production techniques, were issued in 1963 culminating in contracts for mass production in 1965 based on the production methods chosen by the Army. Because the M-1 helmet liner was currently in production the new nylon liners were identified as Combat Helmet Liners.
After issue of the first mass produced nylon liners it was discovered that many of the liners did not marry well with the steel helmet body. Poor fit between the helmet and nylon liner could result from even a slight distortion of the liner body.
Complicating this problem were the minimum and maximum allowable tolerances for the fabrication of both the helmet body and the liner body. If soldiers were issued a liner body produced to the maximum allowable dimension coupled with a helmet body produced to the minimum allowable depth of draw, the helmet body would ride high on the liner.
When a helmet assembly, containing components at the extreme tolerances, was worn with the helmet chin strap unclasped, the helmet had a tendency to wobble on the liner or to separate completely when the soldier was engaged in running or similar physical activity. In order to provide comfort, stability and promote keeping the chin strap clasped, the Army investigated alternative chin strap designs and in 1973 a new assembly of cotton, nylon and steel was chosen as the new standard.
The new design had a cotton open web cup with a snap fastener quick release. This chin cup was attached to a nylon-webbed strap on either side, which acted as adjusting tabs. When fastened and adjusted, the chin strap assembly stabilized the helmet assembly by pulling it tight against the wearer’s head.
The final contract issued for M-1 helmet liners was issued in June 1984 and was split between Stemaco Products and Specialty Plastic Products (SPP). Both have two tone green interiors and black ink stamps with contract information but Stemaco liners do not have a mold-in mark while Specialty Plastic Products have CMP in a circle.
The reason for this is because Specialty Plastics Products purchased the mold tooling from Consolidated Molded Plastics. Along with the CMP mold-in mark will be a black ink stamp containing the Defense Logistics Agency number DLA-100-84-C-4431.
Records indicate that SPP molded their liners to the maximum tolerance allowed and added up to ¼-inch reinforced material to the sides and back of the liner. These factors altered the size and shape of the final SPP contracted liner body in a way that made them the most problematic when attempting to fit them securely into a helmet body.
Big Red Says!
FIVE'S OVER - MOVE OUT!
some SPP liners did have an in mold mark consisting of an SPP. i have one such liner.
That DLA contract was issued to Specialty Plastics Products
on February 1983 for 342,000 Combat Helmet Liners Type 1
The numbers in the circle are production stamps believed to identify the mold cavity.
I BOUGHT A LINER OFF EBAY ABOUT 2 MONTHS AGO AND ON THE INSIDE IT SAYS LINER HELMET GROUND TROOPS TYPE 1, NSN 8470-00-935 6843 DLA-100-83-C-4252, AND IT HAS-17- ON THE RIGHT SIDE CAN ANYONE TELL ME ANY THING ABOUT IT.?, I HAVE 3 STEEL POT HELMETS AND THAT LINER WILL NOT FIT THEM I HAVE TO FORCE IT IN AND IT STILL RAISES THE STEEL POT UP. I HAVE ANOTHER LINER, WITH NUMBER 7 ON IT AND IT FITS ALL 3 LINER’S.
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