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View Full Version : Hornady SST vs Interbond--Point of Impact



30048
08-11-2012, 04:34 PM
I have just started reloading for .300 Winchester. I want to practice with the same loads I will hunt with if possible. I bought some 165 gr SSTs but may want to use some 165 gr Interbonds at some point as well. From what I can see, these are the same bullet except for the internal bonding process for the Interbonds. The ballistic coefficient is the same, the sectional density is the same, they look the same. The only difference is that the Interbond doesn't appear to have a crimping groove.

Should I be able to use these bullets interchangeably and expect the same point of impact, trajectory, etc (the same for everthing except terminal performance)?

versifier
08-12-2012, 04:33 AM
Welcome to The Guide.

No, you should not expect it.

It might happen with your barrel, and it might not.

There is no way to tell without actually loading and testing them in your rifle. It doesn't take much to shift POI, and even though the BC and SD are the same for both bullets, I doubt that the center of mass is also.

The real question is will the POI shift be enough to matter; even an inch or two is still well within the kill zone of a deer at 300yds. Dead deer certainly won't notice the difference.

30048
08-12-2012, 04:48 AM
Thanks, of course I will test them. I was just at the range today testing the start from load, the max load, and a load half way in between for H4350 (not in that precise order, of course). The point of impact was pretty much the same as 180 gr corelokts at 100 yds. Even the max load seemed light and there was no sign of over pressuring the case and the case was no more difficult to extract than the start from load.

I think the Hodgen load data may be a bit conservative and was thinking about switching to RL22 when this runs out anyways. RL22 rates the same quantity of powder for 165 gr and 180 gr bullets and the muzzle velocity is higher for the max load at 180 gr than the max load for 165 gr for H4350. Hodgen requires that you drop your charge when moving to the heavier bullet. This makes sense but, all around, their load data seems to be getting the least out of the 300 winchester compared to IMR and Alliant.

Paul B
08-12-2012, 03:00 PM
I'm thinking they should impact reasonably close and with a bit of luck have both bullets stay in the same group. I don't use bullets that light in the .300 Win. Mag., my preference being with 200 gr. bullets. I use a powder no longer on the market, Winchester Magnum Rifle (WMR) andI shoot the 200 gr. Speer Hot-Core and the Nosler 200 gr. Partition with that powder. Both bullets shoot into one inch or less, mostly less when I do my part. Combined groups though shooting thee of each bullet produced a groups between 1.25 and 1.50" 99 pecent of the time. Worst combo group I ever shot was 2.0" and that could have been my fault. I have the rifle sighted to favor the Speer bullet as I use the Nosler for shots at 200 yards or less and th softer Speer for shots past 200 yards. This has worked quite well so far as the last Arizona elk I shot was dropped at 530 yards laser measured. I usually do serious practice before elk season (when I can draw a tag) with shots in the offhand position at 100 yards and sitting and kneeling at 200, 300, 450, and 500 meters on my club's silhouette range. Usually it's two times a week up to time to leave for the hunt. Yes it's a bit expensive but well worth the effort. On the hunt I have three rounds with the 200 gr. Speer in the magazine and the Nosler up the spout. If the elk is farther out, I usually have time to switch out the Nosler for nother Speer. It's been my luck that when I do draw a tag, it's for an area where long range shots seem to be the rule. it's just worked out that way so I prepare for it.
Dunno for sure just how your rifle will place those two bullets in a combp group with say three of each in the group. Maybe you'll be lucky like I was, maybe not. I'd like to hear about your results though. BTW, my load with that long gone powder does 2930 FPS with the Speer and 2950 FPS with the Nosler. My rifle has a 26" barrel.
Paul B.

30048
08-13-2012, 12:16 AM
I will respond when I try something else but it will be a month or two probably. My 165 gr SST handloads shot about an inch low at 100 yards compared to my factory 180 gr Corelokts. Based on this experience and your experience with two widely different bullets I would be astounded if there was a practical or even noticible difference, however. Everything but the internal bonding process seems to be the same between the SSTs and the Interbonds. First I need to get a better rest instead of range sand bags because I'm yet to get any real accuracy out of anything consistently. While I'm reading that Ruger M77 accuracy can be bad at time (perhaps user error more than anything), I know I've gotten a few sub 1 inch groups from the Corelokts. So it's either a better rest, heavier bullets, or lower velocities but I'm confident I'll get good accuracy from it.