Reloading the 277 Fury 6.8x51 SIG Hybrid Case

[Nine Banger]

Very cool, nice work, does it shoot acceptably well so far?

I haven't zeroed it yet.

My steel is too marked up to really see what's going on.

Real tight schedule.

I'll follow up when I get the fire formed brass dialed in and the rifle zeroed.

 

[Nine Banger]

Very cool, nice work, does it shoot acceptably well so far?

47gr Lever load is ok. Holding velocity. I am still fire forming resized sig brass.

I shot fast and it's really windy here with the 2 hurricanes passing by. So the target is leaning in and out a little in addition to full value 6-9mph wind.

I came down .4 but need to check windage on another day. Prob need to go left .1.

 

[Jimbee]

Just getting started playing with a 243 load. 42gr H4350/95tmk = 2758fps. Factory Tikka superlite barrel cut to 17"

 

[Nine Banger]

I loaded 5 of my fire formed, fl sized and trimmed cases to see if there was a velocity difference from cases that were just scrunched and necked up on the first firing.

It's about the same but ES has shrunk.

I didn't look at accuracy yet. I just shot a piece of steel at 300 with a 1 mil elevation hold.

 

[Nine Banger]

This is Captain Obvious stuff but may help someone else like me that wasn't sure.

The long action bolt stop and 300 win mag factory mags work with the 300 Fury.

I was hand feeding it single rounds up until today when I got the bolt stop in the mail.

 

[wind gypsy]

View attachment 943503View attachment 943503Just getting started playing with a 243 load. 42gr H4350/95tmk = 2758fps. Factory Tikka superlite barrel cut to 17"

Give 'er some gas Jim!

 

[Eric_F]

Update, I finally took a closer look at the gouge in my chamber. It does seem to be a ring dug into the chamber right at the 0.2" line, at the end of the steel base. Again this is just 233 rounds, not insane pressures.

 

[walk2112]

Update, I finally took a closer look at the gouge in my chamber. It does seem to be a ring dug into the chamber right at the 0.2" line, at the end of the steel base. Again this is just 233 rounds, not insane pressures.

Still functions fine and smooth enough?

 

[Eric_F]

Still functions fine and smooth enough?

It's always been a little difficult to chamber and extract (at least partly because it was difficult to form to 6.5 CM), but seems like it's getting worse.

 

[Sundodger]

I wonder if making a slight relief in the chamber where the steel and brass meet would resolve the issue or cause more problems. Like a belted magnum.

 

[Nine Banger]

I wonder if making a slight relief in the chamber where the steel and brass meet would resolve the issue or cause more problems. Like a belted magnum.

I'm figuring our barrel life is going to be 4-600 rounds and who cares?

I was going to nitride my barrel to see if it eliminated this but I jumped the gun and installed it and I've already shot it around 100 times.

 

[wind gypsy]

I wonder if making a slight relief in the chamber where the steel and brass meet would resolve the issue or cause more problems. Like a belted magnum.

No idea but I sure wouldn't want to be the guinea pig with reducing case support on high pressure rounds. I've seen threads in recent years where brass has blown up in pre-fits that didn't have enough case support around the case web.

 

[Eric_F]

I wonder if making a slight relief in the chamber where the steel and brass meet would resolve the issue or cause more problems. Like a belted magnum.

It's making its own relief cut already. To me the concern is then the steel (and brass maybe?) at the washer joint can expand during firing, making it tough to resize and potentially leading to case head separation.

These came off during sizing (not enough lube and annealing) and the remaining brass was almost impossible remove.

 

[z987k]

I've been shooting this a good while now. Probably 500 rounds on this barrel. Throat looks fine. I've not had any case separations sizing like above.

However, the other day bolt lift suddenly got stiff on a load I've been shooting a good while that is likely in the mid 70kpsi range. I also have a load in the all brass case. Put one of those in and no issues at all. So I downloaded some steel case to probably sub 60kpsi, still stiff bolt. Pullet the bullets on a couple to check the powder load. It's correct. Lot numbers on the powder are the same. Loaded a couple brand new cases, still stiff bolt.
Pulled the barrel out of curiosity. It has the ring at the brass/steel junction like everyone is showing. Dragging a pick across it, there's clearly a difference in height. Couple thou, idk. Is that what's causing the sudden hard extraction? Not sure.

I think I might just switch over to the brass case for the rest of the life of this barrel. In all honesty, the extra 125fps I'm getting between the two makes absolutely no difference at the ranges I hunt with this rifle. And makes no difference whatsoever at the range.