This Hesse lower was purchased as a lower for bull barreled target rifle but when I saw the poor quality of the fit and finish of the lower I deemed it unsuitable for a high quality project. The buffer retainer hole is cut too far forward causing the buffer to slam against the retainer with each shot rather than the bolt carrier (see below left). The flat across the top of the upper is arched which causes some uppers to fail to close (see below right).
The Hesse lowers are also cast rather than properly forged like Armalite, Bushmaster, Colt and others. The AR series of rifles was designed to be forged and changing the method of manufacturing to casting without changing the dimensions could lead to safety issues. The crude casting is what causes all the swirls and whirls to show up in the flats and radiuses that ought to be smooth (see below bottom). A cast lower will be flat along the front surface rather than show the milled portion of where the forging hammers meet. Also markings will be raised and crude rather than the finer impressed markings of a forging.
Above - Close up showing the damaged caused by the buffer retainer impacting the buffer with each shot. Notice that the receiver extension is screwed in properly. If the hole was a bit farther forward the buffer would slightly more forward and would ride with the carrier as it cycles forward and backwards. The buffer should be slightly forward of flush with the receiver in this position.
The only cure for this is to mount the buffer in a lathe and rebate the rim of the buffer back. The wear in the center of the buffer is caused by the carrier slamming into the buffer tube rather than riding it back and forth smoothly.
Above Right - The photograph above shows some of the issues on the top surface of the lower. The top arrows show some minor machine work. The one on the left is a gouge, the one on the right is a series of hammer marks - all below the finish “paint”.
The set of arrows below on this picture mark the beginning of the raised area in the middle of what should be a perfectly flat top surface of the upper. An area about 3/4 of an inch long starting at this point is noticeably thicker which causes issues mounting some uppers on this lower.
You can also see a wear area where the hammer is riding the bottom of the carrier.
This picture show some of the other issues with the reciever and a couple others not due to Hesse. To the rear the shoulder stock has a small gap and over hangs below. You can really get a feel for the apsolutly rotten quality of the “paint” job. There are dots, swirls and whirls in the casting which are pretty clearly shown here. Notice the roughness of the trigger hole just above and forward of the top of the trigger. The pistol grip which fits snug on other lowers seems to be miss matched with a gap front and top.
Other issues are not due to Hesse - the safety and trigger guard. The safety doesn’t lock in the 12:00 position rather it locks at the 11:30 position. Its cam is poorly cast causing it to be just that much off. The trigger guard is made of plastic but is also too large aft to allow the installation of a gapper plug. Some like the the plastic guards as they snap rather than bend possibly jamming the trigger out of operation.