Originally Posted by
barrel-nut
Have the gunsmith check the headspace. Sounds like it may be tight. That could explain the difficult chambering issue. Also hot loads would cause tight extraction. I've had factory loads that were on the hot side before I started handloading. Especially if, as it sounds, you may be firing 5-6 rounds without adequate cooling time, and then putting a round into a hot chamber and letting it become hot before firing, might cause high pressures with some powders that are temperature sensitive and may be already loaded at max. Lack of, or poor primary extraction could also contribute to hard bolt pull. Most likely it's due to overly hot loads causing the brass to stick in the chamber.