12 Ga VH sticky opening after firing?

[78CJ]

I finally got around to checking to see if my VH is adequate for Turkeys out to 30 yards. After researching quite a few threads here I concluded that being a 2 frame 12 gauge with my rough measurement putting the chamber at around 2 3/4" that I would use Winchester 1 1/8 oz #4's that are listed at 1250 fps. Knowing that the wood is probably the weak part I only fired 3 round through it (one happened to be my handload from a few years ago that actually patterned better than I thought it would). After each round when I broke the gun open it seemed to stick for about 1/8" and I had to use a little force to get it open. Not a lot but it did not drop open.

Any thoughts?