Oh yeah, I forgot to mention another value to the 'combined' graph. If you look at the ellipse, you'll see that the width is almost exactly twice the height. When this happens, "somehting" is "going on". Either the 'nut behind the butt' is "pulling" the trigger, or the barrel has a bedding problem. Nonetheless, a 4-shot group will hardly tell you that. However, combining multiple groups, especially those shot over some longer interval of time, will indeed tease out subtleties not visible in one or two groups. In this case, it was the "nut behind the butt" sort of. The trigger pull with the 'new' bolt (bent handled one) is horrible. I strongly suspect it is at least 12 lbs. I'm gonna hafta fix that.
 
Paul

Paul, I love what you do with your rifles, great shooting, especially with the taped open sights. I don't know what planet I've been on since this thread commenced, but it makes for some great reading and the awe factor to what you not only do with your tools and machinery but also the narrative and computer assisted analysis.

Great stuff keep it up and if you ever decide to produce anything for the retail market, count me in as a potential customer.

Cheers

Jorge

That's very kind Jorge. Thank you.
 
I was reading over the whole thread again (it helps sometimes to go back over things a few days after the 'heat of battle' is over) and I noticed a couple of things. One was the "100 yd" notation on the first whole target. I've corrected the text. Correcting the image requires more effort, so I'll leave it for a while.
 
The second thing was SakoRick's comments about his M-95. Sounds like he got it shooting to point of aim. Izzat so, Rick?
 
Third, I was looking at the first composite graph, and noted that it is elongated in the vertical while the second composite is elongated in the horizontal. Perfect examples of the value of 'composite' groups.
 
In the first range session, I was using open sights, and the trigger was "OK". In the second range session, I was using a 'scope and the new bolt's sear was horribly stiff. In the first session with open sights, keeping a bead exactly "on" vertically can be challenging. Also, I didn't actually start out the range session thinking I'd be too concerned about small groups, so I was even less careful. Hence, the groups show a vertical tendency.
 
In the second range session, the rifle has a 'scope mounted, and the trigger's release due to the new bolt was terrible. I haven't measured it, but it is stiffer than the Martini, which measures at 11 lbs. The 'scope took care of the vertical dispersion caused by the open sights, but the stiff trigger caused a new problem, one clearly seen in the composite graph.
 
I can fix the trigger pull, and the groups I shoot 'for score' at the next range session shouldn't show any left-right or up-down tendencies. If they do, the cause won't be sights or trigger.
 
I'll post a picture of the ugly beast and it's cartridge later today.
 
Paul

Here are the pictures Jorge - rifle first.
 
It's truly an ugly beast at the moment, but it's gonna get better. The stock will be replaced by one that looks like this :http://www.gunstocks.com/pricemn.html
 
If you look closely at the barrel just forward of the receiver, you'll see a groove. I have no idea why it was put in the original barrel, but I intend to fill it with a "gold" band.
 
Oh yeah, it weighs exactly 11 lbs and 0 ounces empty.
 
Paul

And here are the cartridges. The left is of course the Sierra 220 BTSP for the SLT. The right one is the Hornady 125 HP for the SST.
 
Paul

Which reminds me, I have another bolt with a turned down handle that I can put on the .338 MAI. So... I'm back in the position of being able to bring all three rifles - the MAI, the .375x.284 Win, and the 8mm SLT.
 
We'll see how it goes when I leave for the airport.
 
Paul

Hey Paul,

That rifle looks great. I love the thickness of the barrel. The stock you intend to get will make the rifle look like a Mannlicher Schoenauer, I like that look.

Very nice work.

I've decided to bite the bullet and convert my sporterised portuguese mauser into a 9.3mm rifle. Although it's a small ring mauser the pressure of the 9.3x62 should be fine (I will check with the smith). I won't need to customise the bolt face either. I have found the mounts to fit a scope even with a split bridge. I will use a bolt handle similar to yours. The stock will be the last thing as I will have to get made being an odd configuration but that can wait. Although you can go out and buy a new rifle I believe much joy is derived in producing your own master piece as you would know.

Well done and thanks for share your passions with us dudes on the other side of the world.

Cheers

Jorge

Thanks again Jorge, and good luck with your conversion. Just one thought for your consideration: Given the action, and your willingness to keep the pressures reasonable, would it be simpler to make the conversion a 9.3x57 as opposed to the 64? Just a thought.
 
The SLT's barrel's thickness is one of the reasons I think it shoots as well as it does. In addtition, if you look at the muzzle, you'll see it has a "choke", or enlargement. I think that matters too. In fact, I am pretty sure that the rest of the barrels I order are going to be unprofiled - meaning a cylinder of uniform diameter from breech to muzzle. That way I can profile them as I see fit, including a "choke".
 
I'm working on trying to figure out the "proper" relationship between the bore diameter and the muzzle diameter. The .375x.284 Win's muzzle is not "thin" per se, but relative to the .375 bore, I'm afraid it might be for precision shooting. I think there may be a "proper" ratio between barrel OD at the muzzle, (or wall thickness), and the bore.
 
The down-side of course is weight. Personally, I care little about weight until it gets up to 12 lbs. In fact, I don't like rifles lighter than seven and a half pounds. As I said above, the SLT weighs 11-0 empty.  That ugly plastic stock that's on it is VERY light, therefore I expect the wooden Mannlicher to add enough weight that I will be pushing that personal upper limit of 12 lbs. We'll see. The wooden stock should hopefully add some balance though. Right now, the rifle is pretty nose-heavy. Back on the positive side, the weight REALLY mitigates recoil though.
 
I can't wait to 'poke' something with this rifle. :)
 
Paul

Quote from: gitano;84674And here are the cartridges. The left is of course the Sierra 220 BTSP for the SLT. The right one is the Hornady 125 HP for the SST.
 
Paul

Paul, what is the COAL with the 220 Sierra? It looks great like that, just what I have in mind, though I'll probably concentrate on 200 gr bullets. Sadly any progress on this (& other projects) will have to wait till next year, some git called santa is severely disrupting things just now :laugh:
Steve

The bullet is 1.393" long, the case is 2.353" long, and the distance from the face of the bolt to the lands is 3.265". With those numbers, you can figure any COAL. As always, the max COAL is constrained by chamber length and magazine length. In my case, I wanted about 0.010 to 0.015" of bullet 'jump' to the lands, so for the 220-grain Sierra BTSP we have the following.
 
1) Chamber length minus case length leaves the length available for the bullet to fit into if just touching the lands: 3.265" - 2.353" = 0.912".
 
2) This distance subtracted from the bullet length gives the seating depth that puts the bullet right on the lands. 1.393" - 0.912" = 0.481". Since I wanted to be about 0.013" off the lands, my seating depth was set at 0.494". Keep in mind that this the TOTAL seating depth. The boat-tail length of this bullet is substantial. With the 0.494" seating depth, the length of bearing surface in contact with the case neck is only 0.294". Less than a caliber, but more than two-thirds of a caliber.
 
3) For COAL, it is the case length plus the bullet length minus the seating depth: 2.353" + (1.391" - 0.494") = 3.250".
 
If I remember correctly, the magazine of this rifle will hold a cartridge that is 3.35" long.
 
Here's wishing you luck in getting to the project.
 
Paul

I just thought I would put a punctuation mark on this thread by posting a link to the thread in which this rifle got 'blooded'.
https://www.forum.thehunterslife.com/index.php?topic=12857

Paul

Jeese Louis, has it been that long since you were here last?!!?

How time flies.

RJ

I know. A visit from me "lasts" a long time...
 
Paul