There are two different M27 5.56 links in existence that I know of. For lack of any drawing numbers or other information, I will refer to them as “Type 1” and “Type 2”.
A 24 round belt linked together in Type 2 links will be the same length as a 25 round belt using Type 1 links, i.e. 25 rounds in Type 2 links are ½ inch longer than 25 rounds in Type 1 links.
As a result, if using the Guiette M7M Linker, a different linker plate is needed for each type link. Use the L707 for Type 1 links, and the L707A for Type 2 links.
Same goes for the De-linkers; L708 for Type 1 links and L708A for Type 2 links.
WILLIAM E. GUIETTE
Title II Weapons Manufacturer
TYPE 1 5.56 LINKS-25 RDS.
TYPE 2 5.56 LINKS-24 RDS.
All M27 Links Are Not Created Equal
and Some Are Even "Holey"
With all of the Isreali-modified 7.62 Nato-caliber Browning machinegun “parts sets” which have been imported into the U. S. in recent years, along with the necessary 7.62 Nato links, there is some confusion as to which GMI linker plate is required for linking ammo belts in either .30-06 or 8 x 57 Mauser. When the Isrealis modified the guns from the original .30-06 caliber to the 7.62 Nato caliber, they replaced or reworked the following parts:
Front barrel bearing/booster hole diameter was reduced from .718 to 13.5 m.m. (.531) to make up for lower power of the 7.62 Nato round.
The.30-06 barrel was replaced with a new-manufactured 7.62 Nato barrel. Barrel locking spring notches were re-designed to eliminate accidental rotation of barrel during firing and subsequent headspace changes which can destroy gun. New, matching barrel locking spring was installed in barrel extension.
T-slot in bolt face was deepened slightly to receive thicker rim of 7.62 Nato round.
Belt holding pawl cutout was widened toward the rear from .375 to .555., since with the shorter 7.62 Nato round the links set farther to the rear. A new-manufactured belt holding pawl .550 wide was installed.
Rear cartridge stop was replaced with a shorter one in order to clear the links as they passed to the right and out the ejection port.
A front feedway adapter was installed which effectively moved the bunting surface of the trunnion rearward to make up for the shorter 7.62 Nato round.
A new-manufactured feed pawl, with an arm moved farther rearward, was installed into the feed cover, which was modified by a clearance cut.
The rear sight ladder was replaced by one with the correct range markings for the 7.62 Nato round.
On some guns, a hole was drilled in the left sideplate to allow the insertion of an awl point to pry the barrel locking spring away from the barrel, to facilitate headspace adjustment without disassembling gun.
Trigger frame was modified by the addition of a locking trigger stop screw, for adjusting timing (normally done before by bending trigger bar).
Since the guns as received from the U. S. were already well-used, some of the trunnion pin holes were also reamed out and bushed.
Rear sight guard had plate welded on front of right-hand ear to allow use of screwdriver in prying cover latch rearward, without harming sight ladder.
In order to change the gun from 7.62 Nato to either .30-06 or 8 x 57 Mauser, change the barrel booster back to the .718 dia. (the original .30-06 size); change the barrel and matching barrel lock spring; and install the correct feedway adapter for 8 x 57 or remove it altogether for .30-06. For .30-06, make sure your gun has a "front cartridge stop" (a 5/16" dia. x 5/8" long pin projecting into the front of the feedway from the right sideplate. Everything else can be left alone. .30-06 links will work with (naturally) .30-06, and 8 x 57 Mauser; but not 7.62 Nato. 7.62 Nato links can be used with all three calibers, if desired.
To simplify your linking operation (including ground retrieval), it is suggested that you use 7.62 Nato links for all three calibers. Use the GMI 7.62 BMG linking plate and push the rounds in until the shoulders stop against the small forward loops.
Be advised that the .718 booster was intended for the M2 ammunition (150 gr. Bullet), not the heavier M1 (174 gr.) ammo (which used the .866 booster marked “.30 M1”). Also, remember that 8 x 57 Mauser comes in “light” ball (154 gr.) and “heavy” ball (198 gr.). It would be a good idea to use the “.30 M1” booster for the 198 gr. 8 x 57 as well.
Type 1 links have been around since the 1980’s at least, and are marked “M27”, and will fit the FN “Minimi”, the M249 MG, and the Stoner LMG. Type 2 links are of relatively recent manufacture, and are also marked “M27”, but they are distinguishable from Type 1 links by a small hole through the side of the single loop of the link. Type 2 links have approx. .020 more pitch than Type 1 links.