I ran into a problem finding a accurate seating depth with the 154gr. SST for a M70 so I'm not surprised that its happening with the 139gr. Interbond.

I don't have a comparator or any other tool yet. I usually do good with the standard shape bullets by simply chambering a loose seated bullet in an unsized shell, closing the bolt and making a mark on a rod when it touches the bullet down the barrel. I then close the bolt and mark with an empty chamber. I can do this 10 times and the marks will be in the same spot every time. Then I measure the space between marks.

I back the bullet off 0.010 and I'm in buisness.

Not the case with these bullets. With the 139gr. Interbond it's consistantly giving me a measurement of 3.500. That don't even fit in the magazine by a mile. Same problem with the 154gr. SST. I tried loading Hornady's C.O.L. but it never worked out at the range. I increased the seating depth til the box of bullets was empty and said screw it. Why give chase to something I can achive with a standard shaped bullet.

I'm going to give the 139gr. IB a try tomorrow at the Hornady manuals 3.290 unless someone has a quick reply that may help me before I start loading after dinner.

I've never seen the SST bullet so I'm guessing a little. It is highly likely that due to the tapered shape of the bullet that the length needed to engage your riflings is in fact 3.5". You didn't mention what you were shooting but the 3.29 listed is simply the standard COL for a 7mm mag. I have the same problem with a 300 win mag I load for. The length needed is way longer than the box. So I set it as long as possible and live with it.

I tried 180 SST's for my 300WSM. They are very long and very tapered, so your experience does not surprise me. Load as long as magazine allows or try single feeding, if they don't work, move on. In my experience, you won't be missing too much. I had significantly better luck with Nosler BT's, in both accuracy and on game performance.

Last night I played with the depth til I had no room to spare in the magazine. They are short enough to cycle but as long as I can go without loading problems.

3.375 is where I settled.

Today I tested them and was getting 1.25" 3 shot groups. I worked my way up to Hornady's max of 68.0gr. of RL22. This listing is for the SST not the Interbond. Not bad for fist load tested without having a desired seating depth. I'm going to try another powder tomorrow. After a few powders, I'll try playing with the seating depth with the most accurate load.