275 xpb reloading

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275 xpb reloading

Postby offrink » Wed Sep 25, 2019 6:52 pm

Lots of questions on reloading the 275 xpb and as well as the tsx. From what I have read, and there is very little actual information, the coal is all over the place. From 2.260 to 2.443. And powder loads have been from 32 to 42 grains of lil gun. And similar spread for H110 (still don’t know which is better). Many of the photos seem to be gone now too so I can’t even visually understand what people are trying to do.

So what do people recommend?
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Re: 275 xpb reloading

Postby Hoot » Wed Sep 25, 2019 8:16 pm

offrink wrote:Lots of questions on reloading the 275 xpb and as well as the tsx. From what I have read, and there is very little actual information, the coal is all over the place. From 2.260 to 2.443. And powder loads have been from 32 to 42 grains of lil gun. And similar spread for H110 (still don’t know which is better). Many of the photos seem to be gone now too so I can’t even visually understand what people are trying to do.

So what do people recommend?


Sorry about the images I put up that keep disappearing, thank you Tiny Pic and Google images. I have a good host lined up for the moment but with all the images I have spread around, it would probably take me 2 weeks of evenings just to re-host them and edit all the posts to point to the new host. I will get that done once the baseball season is behind us. Go Twins! Image

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Re: 275 xpb reloading

Postby Bmt85 » Wed Sep 25, 2019 8:16 pm

The main reason is to be able to run more powder, to get more velocity, or more energy down range. It isn’t really needed for bullet performance because the 275 XPB has a minimum velocity rating of 1400fps and the 275 TSX has a minimum velocity of 1200fps.

I personally load the 275 TSX to 2.335” because it catches the first driving band on the bullet. So better crimp, bullet has less jump, and I can run more powder. All around win.
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Re: 275 xpb reloading

Postby offrink » Wed Sep 25, 2019 8:53 pm

So when you say it catches the first driving band are you saying that the middle of the band is where the case mouth is? This is where I was missing out with the photos. And Hoot, its not a problem if you understand the terminology everyone uses. I’m use to using the cannular and putting a crimp there for 44 mag 45 ago, 223, etc...

Thanks for the help!
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Re: 275 xpb reloading

Postby Bmt85 » Thu Sep 26, 2019 1:12 pm

Verry right is the 275 TSX loaded to around 2.335"

Image14437276-7FA0-4BF3-9AB9-27E6B101E89F by https://www.flickr.com/photos/143654137@N05/, on Flickr
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Re: 275 xpb reloading

Postby offrink » Fri Sep 27, 2019 11:21 am

So load it so the last cannular is barely exposed or barely inserted into the brass or am I just not understanding where these rounds like to be seated.
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Re: 275 xpb reloading

Postby Bmt85 » Fri Sep 27, 2019 12:12 pm

Well you don't need to load that long, other members have had good results going off load data OAL. I load longer for multiple reasons, but one of them is because at that length, the driving band ends up just out side the case mouth. This allows a tighter crimp without having to deform the bullet. Don't go too much though, then it might not headspace correctly. I think I take the crimp on those loads down to .473". I'll have to double check that.

If your running an AR you will need to window a mag to load that long, which isn't hard. Also, you won't be able to load much longer than about 2.34" in an AR anyway (with a windowed mag of course).
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Re: 275 xpb reloading

Postby Hoot » Fri Sep 27, 2019 1:51 pm

I usually advise peopleto seat them so that they can drive the taper crimp down into either a cannelure or driving band groove like in this exaggerated diagram:

Image

If the magazine you're using allows the longer length and you're not into the lands, you could load them longer and use the lower cannelure in the diagram. With both the 200 and 275 XPB's I've loaded, I had to use the one closest to the nose in order for them to fit in my "non-windowed" AR magazine.

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Re: 275 xpb reloading

Postby offrink » Fri Sep 27, 2019 6:31 pm

Thanks for the diagram. That’s just what I do for all my other rounds and I figured that would make sense but reading the wide span of oal’s it just didn’t make sense. I have a non windowed magazine so I’ll be putting it in the first band. Thanks for clearing that up. Now if I can just get an idea of using powder load range. 33 to 35 for lil gun sound right? And what range for H110?
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Re: 275 xpb reloading

Postby Bmt85 » Fri Sep 27, 2019 8:33 pm

Check Hodgdon’s site for load data on the 275
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