Squib is a strange word for a bullet stuck in the barrel of a gun. Recently, I had one of my own to deal with in a .38 caliber revolver I was shooting. This is how I cleared it from the barrel.
NOTE: THIS IS NOT A “HOW-TO” VIDEO AND I AM NOT RECOMMENDING THIS METHOD TO ANYONE. I am simply showing how I fixed the problem.
My mistake was firing reloaded 38 Special ammo given to me that I didn’t know who had reloaded. I had a squib on the 4th shot. Instead of the familiar loud report of a .38 Special round, it sounded like a cap gun and I knew immediately that I had a squib.

This squib was particularly bad in the the bullet was stuck halfway between the cylinder and the barrel, preventing me from opening the cylinder and unloading the remaining live round. So I would have to clear it with the live ammo still in their.
First, I tried to use a wooden dowel as the ram to clear the squib. Also, I tried to squeeze it out with a clamp to avoid having to smack it with a hammer. To hold the gun firmly in place, I built a jig using a scrap piece of plywood as a base and some other wood scraps.

The wood blocks were placed to support the gun in all the right places. I use 2” screws to attach the pieces of wood to the base.
I positioned an adjustable clamp to squeeze between the 2×4 block of wood and the end of the dowel and used a scrap of wood to hold up the right side of the clamp.
I squirted a little WD-40 in the barrel hoping it would help loosen things up.
Just in case things went badly, I put on a heavy coat and my forestry helmet with a full face shield to provide some protection against shrapnel if the gun exploded.

Then I tightened the clamp to put the squeeze on this thing. But it would not budge and the stick was bending.
Plan B was to try using a 6 inch 5/16″ carriage bolt for the ram. To protect the barrel from the bolt’s threads, I slipped a piece of heat shrink tubing over the bolt. Even with the bolt as the ram, the squib wasn’t budging under the pressure of the clamp.
So I would have to go to plan C, which was doing what I had hoped to avoid: smack it with a hammer. However, to my surprise and relief, the squib gave way with a few firm whacks of a hammer and was rammed back into it’s shell casing.
The face of the squib was mushroomed from the process of clearing it from the barrel.

Again, I am not recommending this as a safe method to remove a squib. The safest method is to take your gun to a gunsmith.