I'm still working on my first 2017 Range Day thread, but in case folks were considering buying the Lehigh Xtreme Defense 135gr bullets, I felt compelled to pass along an issue I experienced today. It is important to say that issues like this can often be associated with how the cartridges ride in a give magazine as well as the topography of the feedramps your perticular 450b barrel comes with. In my case, both my Franklin and Bartz uppers have nearly identical feed ramps, but those are all I have to compare. They are not your average Rifle or M4 variations, no doubt to perform well with single stack large calibers.
I only had 9 bullets to test with that were generously donated by a member here. Throughout the course of shooting them, I had jams during feeding on about half. Close scrutiny of one of the jamming rounds revealed small indentations indicated by the black circles as best as my smart phone could catch them. On a hunch, I rotated the round in my mag as indicated "Good" in the following image and it stripped and chambered fine. I extracted it and rotated into the suspect position and again it jammed during feed. Again, it fed fine with the "Good" alignment. This has led me to no longer consider those bullets as appropriate at least in my rifles. Controlling how each round indexes as it rises up the column in a magazine is a fool's errand. OK so on to the image:
I'm not certain how far out of alignment they have to be to start or stop feeding reliably. I only tried two orientations to test my gut feeling at the shooting line.
I suspect that the short seating necessary with these light bullets (2.04 COL) causes them to strip, strike the feed ramp and deflect upward with the attack angle being steep enough for the nose to impact the 12 o'clock lug when riding in mag in an X pattern. When riding in the + pattern, the round slips on by the lug and funnels
into alignment further into the chamber. The two circles in the ensuing image would be IMHO, near where the two on the previous image strike and wedge against. The cause is theoretical but the jams were undeniable.
I did not have any of the other weight XD or XP bullets to test with but if Lehigh reads this, feel free to contact me about sending me some free samples. My guess is this bullet was designed around the 45 ACP and probably was never intended for use in an AR 15 platform.