Metallics JBLS20 Bolts 5/16 x 6 Hx Lag Blt St-zn (Jar 50)

The Metallics JBLS20 lag bolt has a measured shank outside diameter of 0.298 to 0.324 inch with 9 threads per inch and a gimlet point. In wood, drill the lead hole to roughly the root diameter of the thread, not the full 5/16 inch shank, so the threads bite rather than spin. Softwoods can take the gimlet point with a smaller lead hole; hardwood needs the lead hole closer to the shank diameter to avoid splitting or snapping the bolt under drive torque.

No. The JBLS20 is steel with a zinc finish and is specified for use in wood in non-corrosive environments. Zinc plating is a mild indoor and dry-location coating; for exterior, damp, treated-lumber, or coastal work you want hot-dip galvanized or 18-8 stainless lag bolts in the same 5/16 x 6 size instead. Treated lumber in particular will chew through plain zinc.

Yes, that is the intended use. The JBLS20 is called out for the electrical, plumbing, heating, and air conditioning trades, with a 60,000 psi minimum tensile strength and a Rockwell B70-B100 hardness from AISI 1006-1022 steel. The 6 inch length lets you get well past sheathing or blocking into solid framing, which is what controls real withdrawal capacity on an overhead hanger.

No. The JBLS20 is a wood lag with spaced threads and a gimlet point, meant to thread into timber. Driven into concrete or block it will not hold. For masonry you need a concrete screw anchor or a sleeve/wedge anchor sized to the fixture, not a lag bolt, unless you are lagging into a lead or plastic shield designed to accept lag threads.

Head width across flats measures 0.484 to 0.500 inch, so a 1/2 inch socket or wrench is the driver for these. It is a full-bodied hex head lag with spaced threads, so an impact driver with a 1/2 inch hex socket is the normal way to run them, not a screwdriver bit.

These ship 50 pieces to a jar, and 50 each is the order minimum, so the jar is the smallest buying unit. Metallics notes other sizes and quantities in the BLS and JBLS lag bolt line are available by request if 5/16 x 6 or a 50 count is not what the job needs.

Head and body dimensions conform to ASME B18.2.1-1996, and the steel is AISI 1006-1022 with a 60,000 psi minimum tensile. Threads are right hand, 9 per inch. That is the data a spec reviewer or inspector normally wants on a lag bolt submittal. Note it is not Buy American compliant and not ARRA compliant, with multiple countries of origin, so it will not clear a federally funded domestic-material spec.

The jar holds lag bolts only, no washers. Use a flat washer under the hex head whenever you are clamping wood or a soft fixture, so the head does not crush into the material as you torque it. Ordering note: the published washer OD figure on the JBLS20 record is 0.125 inch, which is a hole-size type value rather than a washer you should buy to, so size the washer to the 5/16 shank at the counter.

A jar of 50 JBLS20 lag bolts comes in at 5.61 lbs. Handy figure if you are loading seismic or hanger kits onto a cart and watching weight, or stocking a service van with several sizes out of the BLS and JBLS lag line.