Originally Posted by 93trojan
I finally got my 338 win mag back from a reputable builder. He told me that the gun was shooting half inch groups with 225 tsx federal supreme. I bought a lead sled to try some ttsx loads. When after 3 or 4 shots with the ttsx...200 and 225 gr, I would get a flier. I figured that I would stick with the regular tsx and loaded the rifle ready for the hole on top of hole thing. Well, they didn't seem to shoot any better than the other two. I would get an moa 3 shot group Nd then the 4th or 5th shot would drop about 3 inches and to the left an inch or two. Can't figure it out. It was the first time using a lead sled, but it seemed easy enough and quite solid. Anyone else have this happen to them? I was shooting a round a minute for a 4 or 5 shot string and then let it cool for 10 or 15 minutes. The stock, not the barrel, was resting on the front brace.
I'm not a fan of the lead sled. It removes several variables and introduces new ones. But, if your first 3 shots are always tight, it doesn't seem like the lead sled is your problem here.
Try stopping with 3 shots and then wait until the barrel completely cools and try another 3 shot group. If your groups are repeatedly and consistently tight with no fliers and no change in POI, then your problem seems to be stress in the barrel and/or reciever due to heat build up that's throwing your 4th or 5th shot.
Otherwise, it may just be harmonics in the bullet/load/rifle/shooter/lead sled combo. In which case, you need to methodically change one variable at a time to identify the issue.
Or, take the rifle to your smith and observe him shooting it since he said it was on the money.