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Discussion Starter #1 (Edited)
I took my latest T97, Nagoya #6572, to the range today. Fired it using my modern scope mount and a cheap 3x9 simmons scope. Ammo was Graf's and some kindly loaded by DaveF this past winter.

Adjusted the scope at 50 yds after collimating, first target with the first and second adjustment shots indicated, then a 3 shot group of 0.9 inches or 1.8 MOA. See first picture below.

Then moved to 100 yds, the third picture. Interesting, the shots fired had two 'centers' about 3 inches apart vertically. I have read somewhere what causes this, but it escapes me.
I'm thinking bedding or ammo velocity. Made no difference between the two loadings. Acutal measurement of the 'group' is 3" x 1". Called flyer not included. Third picture below.

Maybe Mag can comment.

Scope and rifle mount shown in picture two

Still good performance I think, deadly if shooting at a human target.
 

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On the second target with 2 distinct groups, could it possibly be caused by the scope? Maybe the crosshairs slipped a bit inside after a few shots. Or maybe the made up mount moved some. Could be bedding after the barrel heats up and the vibrations change, but would think that the hits would start stringing up and not clump like that.
 

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That could have been caused by several things. A bedding problem that causes a shift as the rifle heats up, the way to check is to shoot a few and let it cool before the next few. It could be a scope problem, the crosshair gears skipping under recoil, or the mount.
The Flyer did not hurt your group size as groups are measured by the center of the two farthest bullet holes. It could also be the load, powder or bullet. After test shooting 10,000"s of groups , my friend and I have what we call the 20% rule. If a load is not working just right it will throw about 20% of the shots. The "bad" load is not quite sabilizing the bullet, so about 20% will start to angle off, mainly to the same place. This is very clear after many groups with a load. Also a 50 yard group does not mean much as most of the thing that go wrong with a load happen after 50 yards. I just did a bunch of test shooting with a 1899 Gew-98 rifle. I had one load that did a .073 group at 50 yards [ to find the paper and sight setting ] but the same load did an average of 3.86 at 100 yards. The same rifle did a 4 group 100 yard average of 1.34 with another load that did work well, best 1.06, worst 1.54 . Sometimes it does take a while to find the "right" load for a rifle. I hope this gives you some ideas where to look. mag
 

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Probably bad ammo,Don, The stuff I made may not be right for your 97,For me at least a dead on load in one gun may be awful in another.I can send a wider variety of loads for you to try ,as soon as I get back to "cooking".I have both flat based and spitz on hand in 140 and 120 gr .264 or if you slug it I can try to match whatever you need,.257,.268 etc.I can even adjust OAL or olgive lenth (OR BOTH)also if need be to best suit your rifle.DAVE
 

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Discussion Starter #5
Thanks all for the comments.

Mag,
I was not really clear about how the groups came about, first shot was one of the low ones, next two up high, then another low one, then two more up high.The Flyer was last, and mentioned only because I knew the aiming point was off.

Probably eliminates the scope to my thinking, mount is rock solid. May be the bedding or the shooter I suppose.

I'm going to try this again with the same ammo and my 'good' shooting T97.

davef,
thanks for the offer, I don't think it is your ammo. Would be good to have some flat base bullets though. I'll slug and mike the bore to double check, though these late Nagoyas should have the small bore.
 

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Don, I have shot bench rest and it can be anything, one thing, or several things.

Every single thing must be consistent and unchanging. This means no screws should loosen anywhere. The stock pressures at all points must always be the same(better still no pressure except at a synthetic stock bedding or pillar bedding of the receiver and a free floated barrel). The humidity, the temp. of everything including the barrel should be the same with each shoot. The barrel should be cleaned every shot ideally or at least with minimal fouling and that degree of fouling each time(less than 50 round per day). Each piece of brass should be near perfect and weight the same, have the same length and be from the same lot. Only match grade brass will give match grade results. Every bullet should be the same weight and from the same lot. Every load should be exactly the same amount of the same powder and only match grade primers used. Each rifle may like different powder types and charges, brass, bullets, etc.. This requires a lot of trial and error. It is a PIA to get the most out of a rifle but every variable must be eliminated.

Other variables include-- where you put the rifle on the rest, where you rest your cheek, what is your eye relief and how centered, at what cycle is your heart beat, etc. etc.. Again, all variables must be minimized or eliminated.

Getting the most out of a rifle is very hard work and an art and a science. It requires a good bench rest, good optics, good shooter, great rifle and a lot of work. Without hand loading the ammo, I have had good results with Norma and nothing else. I always check all the action screws and apply most of these things to reduce many of the other variables. It is work that can produce nice results.
 

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Discussion Starter #7
Thanks to all,
I'll stick to my better shooter 97 and try to optimize it, it does have a better bore than the one I shot yesterday; and I'll take some norma ammo with me next time too.

Since I don't handload, I'll be at the mercy of davef in that regard.
 

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ILL get some flat based rounds built and sent ASAP ,I know I have the 139gr privi .264's that I got from you .I also have some sierra Match maybe one of those will work well.I low on I-4350 (will go 36.2 grs per Mags notes),but will get a can when I go to town,will build some with I-3031 also (31.5gr works well for me).
 

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Discussion Starter #9
Thanks Dave, we will see what works.
 

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Whats the difference between I-4350 and I-3031 powders? Does one burn faster than the other?
 

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With a 140 grain bullet the load is 36.2 of I-4350. The 28 ish grain load is for H-322 .

I-4350 is a slow burning powder, about as slow as you would want to use in a 6.5 to 8mm siae case. I-3031 is a mid range powder that can give great accuracy, BUT is fast enough where you will start to get high pressure signs before you reach the max velocity with many military size cases. mag
 

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Please correct the one load in the T-38 posting. I typed the loads correctly the first time I stated them, but when I talked about the match I put 28.2 of I-4350, it should be 28.2 of H-322. SORRY, I missed that in the proof read. mag
 

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03 Man, I can not edit the T-38 reloading post as you reposted it. To try and be clear enough about what you need to edit on my post for me. The load shot in the match with the T-97 should be the Lapua 139 bullet with 28.2 of H-322, as stated just before in the post. 28.2 of I-4350 is TOO light. I am sorry about the misprint and not catching it, even with a proof read. Thank you, mag
 

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Thanks Mag, I changed it in the notes I copied into my load book from the post. Ive never worked with H-322 but will get some when I go powder shopping.Is there enough differnce between match primers and normal large rifle ones to justify using them ? Thanks,Dave
 

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Discussion Starter #15
Mag,
thanks, I will change the load as noted.
The thread is locked to prevent such changes; any time you want to add to or edit let me know and I can unlock it for you.
 

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Alot of the things benchrest shooters do or use do not really help with old military rifles. They are just not exact enough to gain anything. You can not get close to the rifling with the bullet seat , the chamber neck is way too large for the case neck, and so on. Regular primers are just fine. I have tried H-322 powder in a lot of military calibers, with good results in most. I used H-322 to load the 6mm PPC and .222 in benchrest rifles. The 6.5x50 case is similar to the 6mm PPC case. ALSO, I forgot to ask 03 Man what type of rest he was using. If you do not have a good front and rear rest you can not get good , repeatable groups and will have flyers. As stated in the other post, gun handling is very important. Guns WILL shoot somewhere else if the are held different shot to shot. I am glad to see at least some people are shooting their old rifles, I wish you guys were closer so you could shoot in some of our matches. mag
 

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Discussion Starter #18
mag,
I use a front beanbag rest and my shoulder for the rear.

Headed out tomorrow with the 'good' 97 and 3 ammo variations; we will see how it goes.

Again thanks to all for the interest and info.

Side note on Japanese rifle bedding: the bedding seems to violate all the 'rules' for accurate shooting: the barrel is neither free floating or under constant pressure, the front band may or may not contact all around the bbl. Go Figure.
 

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You should get a good rear bag, it is a must for accurate shooting. The rear is more important than the front. You can get a good rear rabbit ear bag for around $15.0 or so. I have scored 1000's of match targets and have seen that anyone that does not use a rear bag gets flyers . Arisaka's are in effect " pillar " bedded. There are alot of myths floating around about how military rifle barrels should fit the stock. The fact is if there is more than a little pressure anywhere on the barrel, when it heats up there is more pressure in that spot and that causes changes to point of impact of the bullet. I build rifles and have a lot of experiance bedding actions of many types . Good luck on your shooting and tell us about the results. mag
 

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I was thinking about my last posts on shooting. I hope you do not think I am being hard on your shooting. I am trying to pass on what I have learned the hard way over the years. I have been lucky to have had some good teachers and to be able to shoot in at least one local match every weekend for about 15 years. I have been able to shoot with and learn from some of the best at national benchrest matches. I shoot about 300 rounds every week with old military rifles, and up to 600 on a nice three day weekend. I do not expect others to be able to do that, so I try and work with them at their level. That is why I thought to ask about the rear bag. I use a $600 Bald Eagle rest, I do not expect others to , but there are other easy ways to improve your shooting. I know I shoot a lot more than what is "normal". I just hope this is all coming across as positive. Everybody has their own level of shooting, the friend I did all the test shooting with makes me look like a slacker. He shoots about 200 rounds every DAY of the week and has been shooting like that for about 40 years. He has about 200,000 recorded 5 shot groups in his records. mag
 
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