7.7 Japanese

AJC1 said:
I don't even have a dust cover, my grandfather had the original bayonet but I have a diffrent one, no sling at all here.... mine hasn't been shot very much over the years, but I wanted to put a few hundred rounds through it with my son before it goes to the back of the safe.
Click to expand...
Just having that provenance is an awesome thing!!!!
 
Has anyone read or come across a .22lr scope base that would clamp onto the T99 dust cover grooves. I'd like to mount a scope on my T99 for test load purposes without drilling into the rifle or removing the rear sight.
 
Back in the 60's if I recall there were 2 different size slots, 3/8 & 5/8"?. Most of these scopes had a 3/4" tube back then. You can still buy bases with this clamping system the last time I checked, Weaver makes them. 1" tube size is what I have to fit an old Browning ATD. I replaced the barrel so I could use a cantilever mount attached to the barrel vs receiver, which is way better on this old gun.
 
Got out today.

PPU cases, CCI #200 primers

IMR4064 39.0gr - Hornady #3120 150gr SP - 3.025” COAL

2143, 2151, 2195, 2145, 2162

IMR4064 42.0gr - Hornady #3130 174gr RN - 3.025” COAL

2277, 2288, 2263, 2278, 2283

Caldwell Chrono app didn’t want to cooperate today, so hand written velocities are all I got…
Guess it’s Garmin time…!!!


On the lower side to see where I am at.
Gonna up the charge and have a go… :)

Fired cases:
IMG_0495.jpeg
Sized cases:
IMG_0497.jpeg
 
Last edited:
Soonerpesek said:
Got out today.

PPU cases, CCI #200 primers

IMR4064 39.0gr - Hornady #3120 150gr SP - 3.025” COAL

2143, 2151, 2195, 2145, 2162

IMR4064 42.0gr - Hornady #3130 174gr RN - 3.025” COAL

2277, 2288, 2263, 2278, 2283

Caldwell Chrono app didn’t want to cooperate today, so hand written velocities are all I got…
Guess it’s Garmin time…!!!


On the lower side to see where I am at.
Gonna up the charge and have a go… :)

Fired cases:
View attachment 1197362
Sized cases:
View attachment 1197363
Click to expand...
Which bushing did you use, .400 or .375?
 
AJC1 said:
I don't know if my gun is out of spec, or the brass just way oversized. I going to make some brass with 30-06 and find my headspace... if the rain keeps up that's tomorrow's project.....
Click to expand...
I did buy some loaded rounds from a place.
I measured with the comparator and they were .012” under my fired brass.
New PPU brass is sized .010” under.
So I guess in theory the first firing will be somewhat of a fireform….. :p
I can get some new brass to you if you’d like…
 
Yes… I’m still in the 7.7 club! just gotta finish up the 9mm 147 RMR test load 1st
 
So I annealed the crap out of a federal 30-06 case and commenced testing. By comparator I started at 1.955 at the .375 datum and walked in between .002 and .003 at a time. It finally cammed in when I got to 1.938. The brass was soft enough when it came back on it measured 1.936+. So I know my chamber length and the reason I was getting case head seperation... a new piece of Norma never fired is 1.911, that's a huge leap!!!! 17094931796994959842978416021758.jpg 20240303_132616.jpg 20240303_140715.jpg
 
Soonerpesek said:
Got out today.

PPU cases, CCI #200 primers

IMR4064 39.0gr - Hornady #3120 150gr SP - 3.025” COAL

2143, 2151, 2195, 2145, 2162

IMR4064 42.0gr - Hornady #3130 174gr RN - 3.025” COAL

2277, 2288, 2263, 2278, 2283

Caldwell Chrono app didn’t want to cooperate today, so hand written velocities are all I got…
Guess it’s Garmin time…!!!


On the lower side to see where I am at.
Gonna up the charge and have a go… :)

Fired cases:
View attachment 1197362
Sized cases:
View attachment 1197363
Click to expand...
Did you zero your dial on the comparator, it looks like your cases are even longer than mine????? Probably why these are not considered precision measurement tools....
 
AJC1 said:
Did you zero your dial on the comparator, it looks like your cases are even longer than mine????? Probably why these are not considered precision measurement tools....
Click to expand...
I did not…
The new cases I have are close to what your last pic shows.
The fired cases are .012-.013” longer, so that’s what I based my sizing from…
They are as precision as we need them to be.
I may be using it wrong, but I don’t look for a definite measurement, just something for comparison…
 
I got to buisness this afternoon performance (aka wrecking) 7.7 cases from a stash of federal 30-06. I truly think in the long run I'll get better performance, safer not asking a case to grow .025" My forming effort wasn't exactly uniform with about .003 variation depending how heavy the lube was building up in the die. This was my first case forming effort, so I wasn't exactly easy on the lube. Step one should have been trim off .025" but I found that out screwing them up. The case neck ends up longer than the die and the expander should be removed if using Lee dies. The second thing I learned is a standard parting tool isn't great for trimming cases. After trashing more than a few I broke out the grinder. I started by adding some positive rake. That seemed to help and less pressure was needed. I screwed up a few more and I ground a 45 on the face making a point. That was the ticket. I didn't trash another case after. After they were formed I put back in the expander and ran them all through again. Then I gave them a finish uniforming trim at 2.264 and chamfered and deburred the lot.... my happy butt is sitting on the couch as they get wet tumbled to get off all the lube and the rough edges get cleaned off.... 20240304_190421.jpg 20240304_190443.jpg 20240304_195232.jpg
 
AJC1 said:
The second thing I learned is a standard parting tool isn't great for trimming cases
Click to expand...
Instead of parting them off, would turning them down be an option...?

Come to think of it.....................you have the Lyman case trim express don't you...?

Finished product looks good from here, tho............
 
Soonerpesek said:
Instead of parting them off, would turning them down be an option...?

Come to think of it.....................you have the Lyman case trim express don't you...?

Finished product looks good from here, tho............
Click to expand...
I was trying to quickly take off the excess so it would fit in the sizing die. My biggest problem is lack of knowledge and experience on the lathe. I used a collet to hold them and a collet stop to get uniform results. Once I fixed myself it went fast and smooth.... I stopped, went back to basics and broke out the bench grinder....
 
AJC1 said:
I got to buisness this afternoon performance (aka wrecking) 7.7 cases from a stash of federal 30-06. I truly think in the long run I'll get better performance, safer not asking a case to grow .025" My forming effort wasn't exactly uniform with about .003 variation depending how heavy the lube was building up in the die. This was my first case forming effort, so I wasn't exactly easy on the lube. Step one should have been trim off .025" but I found that out screwing them up. The case neck ends up longer than the die and the expander should be removed if using Lee dies. The second thing I learned is a standard parting tool isn't great for trimming cases. After trashing more than a few I broke out the grinder. I started by adding some positive rake. That seemed to help and less pressure was needed. I screwed up a few more and I ground a 45 on the face making a point. That was the ticket. I didn't trash another case after. After they were formed I put back in the expander and ran them all through again. Then I gave them a finish uniforming trim at 2.264 and chamfered and deburred the lot.... my happy butt is sitting on the couch as they get wet tumbled to get off all the lube and the rough edges get cleaned off....View attachment 1197781View attachment 1197782View attachment 1197783
Click to expand...
What are you even doing?? you when to
town for a hand full
of brass

brass looks go tho
 
AJC1 said:
I was trying to quickly take off the excess so it would fit in the sizing die. My biggest problem is lack of knowledge and experience on the lathe. I used a collet to hold them and a collet stop to get uniform results. Once I fixed myself it went fast and smooth.... I stopped, went back to basics and broke out the bench grinder....
Click to expand...
I use a right hand facing tool. But that’s just me.
 
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