Reloading for the new .277 Fury from Sig

I'm always scared that I'll be the "dummy"……find it later, thinking that somehow I failed to include it with my last loaded ammo!

Then use it on the best, biggest trophy animal I'll ever see! 🤦‍♂️ memtb
I do need to bump up my load. I used 39gr of BL-C2 and only getting 23xx-24xx fps. I went pretty conservative. (Range 36-41.2) My next loads will be 39.5 & 40gr.
 
I just looked back at the data from xxl-reloading to make sure I remembered correctly, but they were waaaay off, at least with my rifle. I can't remember the barrel lengths they used, but I'm running 16" and just a bit under 80k, but below for sure. If I used what they had suggested I'd be around 2200-2300 fps. They are very conservative, it's a reference for sure, but they seemed so far off, it wasn't really even a reference. Use some of their powder/bullet combos for 308 or 6.5 and compare to what several other books have for max and min in those calibers. You will notice xxl-reloading is completely different. Their max, it seemed was as much as 2-3 grains of powder or more below what other manuals listed.... and 2-300 fps slower too, which would seem obvious. Moral of the story was that their max pressures didn't line up with any of the other reloading manuals I had. Just FYI and something to research.
 
I just looked back at the data from xxl-reloading to make sure I remembered correctly, but they were waaaay off, at least with my rifle. I can't remember the barrel lengths they used, but I'm running 16" and just a bit under 80k, but below for sure. If I used what they had suggested I'd be around 2200-2300 fps. They are very conservative, it's a reference for sure, but they seemed so far off, it wasn't really even a reference. Use some of their powder/bullet combos for 308 or 6.5 and compare to what several other books have for max and min in those calibers. You will notice xxl-reloading is completely different. Their max, it seemed was as much as 2-3 grains of powder or more below what other manuals listed.... and 2-300 fps slower too, which would seem obvious. Moral of the story was that their max pressures didn't line up with any of the other reloading manuals I had. Just FYI and something to research.
xxl-reloading.com is their old site. Look at xxlreloading.com They have a section that you can change the length of your barrel and look at what those results. They do use a strange barrel length as their default. I believe 23.6". Also, if you look at their calculations, they use a 10% buffer (adjustable) when giving you a range of powder measurements.

Using their site, I was able to get a starting point for loads for my 277. No one else has any data for this load.

I emailed Hodgdon and asked if they had anything; their response was no, they didn't have any data for the 277 Sig Fury.
 
Just my 2 cents here but I had some damaged hybrid cases with the 113gr projectile. I pulled all 4 rounds and found the powder charge at 50.5-51.5gr in all four cases. This is 6.8x51 fyi and the powder is definitely a mix of ball and cylindrical powder. I do have some conventional cases 135gr ammo I could compare it to. Hope this helps
 
A mix of ball and cylindrical.... interesting. I'm curious what companies with true pressure measurement devices end up publishing with temp insensitive powders like 4350, varget and so-on. I've seen over the years guys getting pretty impressive speeds with sensitive powders, but I'm not too interested in something that shoots 40 inches lower hunting than when I developed and "trued" my data. If I remember correctly, the faster, higher pressure 7 SAW was getting pretty impressive results with Varget which is pretty stable. I'm curious if there is anyone out there who knows how high the pressures they are running in those SAWs are? I thought about running it back in the day and using the srp to enable higher pressure but didn't like some of the feedback about ignition at super cold temps.
 
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