Strength of sewn loops girth-hitched to 1/8" Dyneema/HMPE slings
(HMPE is high modulus polyethylene, as in Dyneema and Spectra; much is now unbranded, from China.)

The loop itself never broke in these tests, so this is really a test of the strength of the loop-sling-girth hitch combination.

I keep a small sewn Dyneema (Amsteel) loop in my pack "for emergencies." The loop is made from 4000 lb-test 5/32" Amsteel, and is < 3" in diameter- much smaller than could be achieved by splicing. In the picture below, one sees only the stitching on an outer tubular nylon sheathe. The sheathe is slipped over the stitched 2" overlap of the ends of the Amsteel, and the outermost stitching penetrates both ends of amsteel essentially perpendicular to the stitching previously used to join the ends (discussed here). The outer nylon is saturated with urethane, then coated with PTFE on the inside of the webbing tube. The sheathe increases total abrasion-resistance, and is a significant thermal protection for the Dyneema inside. The total weighs about 0.2 oz (a 3/16: stainless steel quicklink weighs 0.7 oz), so it is a convenient emergency item. I can use it to connect the spliced eyelets of an HMPE eye-to-eye sling, or put a girth-hitched loop over an existing (rapideless) 1" nylon sling.

The loop is put through eyes of an eye-to-eye Dyneema sling (or over a piece of nylon webbing);



The setup for the 2nd test is shown below; the 1st test differed only in having a soft shackle in place of the bow shackle:



Two tests were performed.


In the first test, breaking of the sling was just below 3000 lbs, and not in the girth-hitched section. However, this test used an Amsteel soft shackle  instead of the bow shackle, and the HMPE sling broke at the tight bend around the soft shackle:



In the second test, the Amsteel sling was over a 3/4" bowshackle instead of a soft shackle, and broke in one sling eyelet at about 3400 lbs.

Only after the 2nd test, was one yarn in the sewn loop slightly abraded.