The stuff they make the plastic sabots out of will not melt when shot. If you recover some of your sabots, look at the bottom of them at the shot cup. Check to see if there is burned spots (not just powder stuck there) and small fissures where the plastic has actually failed and cracked or split. If there is, that means the load is too hot. You would then need to put a buffer between the powder charge and the sabot to take some of the heat off of it. Or you could change your powders or cut your charge. Another option is to go to thicker sabot if you can. Sometimes for reason of accuracy this is not possible.

This is a good reason for swabbing the barrel between shots. It gives the rifle a chance to cool down and wipes a lot of the crude that would othewise build up in the barrel. Although on a hot day I have had the barrel so hot, you would not want to hold it. I usually shoot a couple rifles on those days and while one rifle is cooling in the shade, I shoot a different one.

You can get a build up of plastic in the barrel of the rifle and it can happen faster then a lot of people think. This can especially on a hot day when your shooting a lot, the barrel has no time to cool down. The result is it the sabot will softened from the heat. The plastic sabot is worn off as it travels up the rifling and it lodges in the lands and grooves of the barrel.

This is why when you clean your rifle, always use a brass bore brush and a quality solvent when you scrub the barrel. It will remove the copper, lead, and plastic fowlings found in the barrel. I use Butch's Bore Shine right now, but prefer Birchwood Casey Bore Scrubber. (I ran out and bought some Butch's at Wal Mart... works good actually). Again, remember... after you have used a strong solvent to scrub the barrel it is very important to be sure and coat the inside of the barrel with a quality oil even for short periods of storage. I use Birchwood Casey Sheath. This stuff really works and comes right back out before shooting the next time with a patch soaked in denatured or isopropyl alcohol and windshield washer fluid. Two dry patches then and your ready to shoot.