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View Full Version : KOMBI, Where are you


Alboy
08-09-2008, 01:27 PM
http://re3.yt-thm-a01.yimg.com/image/25/m4/2987075092 (http://rds.yahoo.com/_ylt=A0geu78v4Z1ITWEAx1BXNyoA;_ylu=X3oDMTBscWN2ZnB jBHNlYwNzYwRjb2xvA2FjMgR2dGlkAw--/SIG=1ip44q1qo/EXP=1218392751/**http%3a//images.search.yahoo.com/images/view%3fback=http%253A%252F%252Fsearch.yahoo.com%25 2Fsearch%253Fei%253DUTF-8%2526p%253Dkangaroo%26w=800%26h=600%26imgurl=www. 7art-screensavers.com%252Fscreenshots%252Fwild-animals%252Fkangaroo.jpg%26size=143.5kB%26name=kan garoo.jpg%26rcurl=http%253A%252F%252Fwww.7art-screensavers.com%252Fscreenshots%252Fwild-animals%26rurl=http%253A%252F%252Fwww.7art-screensavers.com%252Fscreenshots%252Fwild-animals%26p=kangaroo%26type=jpeg%26no=1%26tt=449%2 52C406%26oid=8a3eaba81629b80e%26tit=kangaroo.jpg%2 6sigr=11pg8ourh%26sigi=11vbk6egk%26sigb=11imeoibq) :greentongue: :sleeping:

Brithunter
08-10-2008, 02:31 AM
He's probably sneaking up on the Roo with the "Judge" :greentongue:


Oh the forum will be fine as long as there is no "Fosters" about:smiley:

kombi1976
08-12-2008, 10:39 PM
Fosters??!! :eek:
Get thee behind me, Satan!! :mad:
I'll have to nail a roo with "The Judge" although I'll have to be carefull where I do it.
If it punched through a goat like it was rice paper it'll cut through a roo like a hot knife through butter! :confused:
I'll have to save it for a chest shot on a really big male although I reckon it'll exit just the same.
A mate got freaked out badly the other day when he nailed a fox with his 8x57 using a 170gr and he heard the bullet hit a fence post 40m behind.
He switching to 125gr HPs for it.

Brithunter
08-13-2008, 03:47 AM
A mate got freaked out badly the other day when he nailed a fox with his 8x57 using a 170gr and he heard the bullet hit a fence post 40m behind.
He switching to 125gr HPs for it



Errrr I thought your mate had slightly more gumption that that :shy: there ain't a Fox born that going to stop a 170 grain bullet out of most decent cartridges let alone the 8mm Mauser :frown . Anyway lets hope that the 125's proove accurate :) but I do think he might find it a little like pushing water uphill :greentongue: Gitano has had no success in getting good accuracy with them.

kombi1976
08-13-2008, 05:41 AM
Well, your right about a fox stopping a 170gr pill but one would think it may slow it down a tad.
Not so with the 8x57.
And I've heard about Paul's problems with the 125s.
You almost need to build a rifle to shoot them....ie a short throat.

gitano
08-15-2008, 11:16 PM
I don't think the 125 will be stopped by a fox either...

Speaking of the 8mm STS (Short-throated Steyr), I may be able to get to the range with it this weekend. If I do, there will be 'pictures at 11".

Paul

kombi1976
08-16-2008, 04:20 AM
I'll be very interested to find out.
Tell me, is there a reason the throat on military 8x57s is so long.

gitano
08-16-2008, 12:03 PM
Actually, after posting the above, I realized that of all the barreled actions I have put together recently, the 8mm STS is the one without a stock. It's the 8mm LTS (Long-throated Steyr) that is going to the range this weekend with the 195 Hornady and the 220 Sierra.


is there a reason the throat on military 8x57s is so long.


I'm just guessing, but I think it is due to:
1) Many 8mm Mausers were "coversions" from .318" groove diameter to .323" groove diameter
2) Arms intended for battlefield use often have slightly larger chambers and slightly longer throats so a dirty chamber doesn't prevent chambering a round and ultimately shooting the rifle, and
3) Early 8mm Mauser cartridges were loaded with 196-grain (long) bullets that required longer throats.

Items 2 and 3 above, when combined, leads to a long leade. :)

Paul

kombi1976
08-17-2008, 10:45 AM
Fair enough.
I wonder if you could overcome that by anything except doing the STS job you did, Paul.

gitano
10-04-2008, 10:59 AM
Gee, this was a bit ago, but somehow I missed it.

I s'pose - but I'm just 'free-wheelin' here - you could take, say a .30-06 case, and run it trough an 8x57 full-length resizing die. That would make a very long-necked 8x57 case. Then, after casting the chamber with Cerrosafe or sulphur, you could trim the case both to length AND thin the front end of the neck so that it fit in the leade with enough room to allow the neck to expand enough to release the bullet.

Of course this is all a 'bit much' just to shoot light-for-caliber bullets, but it would be an interesting exercise.

One other 'stream-of-consciousness' idea is that you could have sabots made that resembled a 'heeled' bullet. 'Heeled' bullets were used from the mid 1800s through the "Schutzen" era. They are still cast today, but only rarely, or by those that are recreating a "period" firearm. I did that with the Collath 'til Drinksgin suggested that I try the .44-40 which was a good substitute for the original 10.75x47.

You wouldn't use a "heeled" bullet in the 8mm because that would defeat the purpose of "light-for-caliber" and is of course unneccessary. However, if you had a sabot made of plastic whose narrow 'heel' fit in the case neck and held the 125-grain bullet forward into the leade, you could I suppose shoot the light-for-caliber bullets. Again, a great deal of trouble just to shoot 125s accurately. If I was going to go to the trouble to make 8mm sabots, I'd just make them to shoot .308 or smaller caliber bullets. Going even lighter in a light-for-caliber bullet.

Finally, there is of course the option of taking the barrel off, turning off a thread or so, and reaming the chamber a bit forward to shorten the leade. I assumed you didn't want to do that, as it means that any bullets heavier than about 175 will be seated pretty deep.

I have actually given up trying to shoot 125s out of milsurp 8x57s. SakoRick has some short-throated milsurp 8mms that might shoot the 125s precisely, but I don't. As for me... well you know the solution I have chosen.

Paul

kombi1976
10-08-2008, 10:16 AM
Ummm, I understood enough of that to understand what you mean......I think?
I do get the point though.
The problem with most of the game I hunt is that a 180gr is overkill.
So I'm going to chase the best accuracy I can within the 125-180gr range.
If the heavier bullets have to be seated deep, well, I can always use the 9.3x62, right?

gitano
10-08-2008, 12:30 PM
Sounds 'right' to me.

First though, I wouldn't give up - so to speak - on the possibility that your rifle will shoot 125s (or 150s) 'good enough' for your applications. Just because mine and a few others don't, doesn't mean yours won't. You may even find that your rifle "likes" light-for-caliber (LFC) bullets. Guns are a lot like women... there's no tellin' what they may end up likin' or doin'. :confused: (Look who your wife ended up with... :greentongue: :D)

Given your practical application of LFC 8mm bullets, it's worth your while, in my opinion, to 'play around a little' with LFC bullets and just make sure your rifle(s) won't shoot them well enough for your needs. It's entirely possible that they'll shoot "like lasers". Stranger things have happened.

Paul

Jorge in Oz
10-08-2008, 08:29 PM
Hey Paul,

I have two Portuguese Mausers which are small ring conversions from 6.5x58 to 8x57. Do you think they would shoot the 125 grainers well. I don't quite get the short throat vs long throat technicalities. I'm in Kombi's situation where I don't even shoot 180 grainers in my 303, let alone the 8mm.

Cheers

gitano
10-08-2008, 09:47 PM
In answer to your question Do you think they would shoot the 125 grainers well. I don't know. Here's why...

The throat is that part of the chamber immediately ahead of the case mouth and immediately behind the point at which the rifling starts. This area is also called the "leade", and the "freebore". It is that area where the bullet sits when the round is chambered.

Some chambers are cut with a long throat, meaning that there is a "long" distance between the case mouth and where the rifling starts. If the throat is "long" and the bullet is "short" (like a LFC 125-grain 8mm is), the bullet has to "jump" to engage the lands. Some folks believe that "jumping to the lands" leads to poor precision (accuracy). Those same folks believe that being "close" (a nebulous value) to the lands, but not touching them, leads to the best precision (accuracy). So...

1) If the fellow that chambered your 8mms figured you would be shooting "long" (AKA heavy-for-caliber bullets), he probably cut the throats long, or the more likely case,

2) He just used the reamer he had on hand which had an "average" throat. In which case, you'll have to seat LFC/short bullets "out", and HFC/long bullets "deep".

You can check the throat length on your rifle three (at least) ways.

1) Buy a Stoney Point Chamber-All. (I think Hornady bought them out, but they're still referred to as "Stoney Point".) I strongly recommend this. It is an excellent tool for the reloader. http://www.midwayusa.com/Eproductpage.Exe/showproduct?saleitemid=570611

2) Cast the chamber using Cerrosafe. http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=462291
This is even better than using the Stoney Point Chamber All, but is a bit more 'involved'. Let me assure you you CAN NOT hurt your rifle with Cerrosafe. Among the advantages of getting a chamber cast is that not only do you get a VERY precise measurement of cahamber length, you also get a 'look' at all the chamber dimensions.

3) Take a FIRED case, and drop the longest/heaviest flat-based 8mm bullet you have in it. Don't worry that it drops inside the case. Stand your rifle on it's butt - muzzle up. Chamber the round. Turn the rifle muzzle down so that the bullet drops 'til it engages the lands. Insert a dowel (quarter inch works well) in the muzzle and carefully run the dowel breachward until you just engage the bullet. Mark the dowel at the muzzle. Remove the case/cartridge and reinsert the dowel 'til it touches the face of the bolt. Mark the dowel at the muzzle again. Measure the distance between the two marks on the dowel. This is your maximum cartridge length for that bullet.

If you seat that bullet in a resized case to the measured length, you can determine the throat length by measuring the total length of that bullet (not cartridge), the bearing length of that bullet, and the max length of the cartridge as determined by the dowel method. The distance from the start of the bearing diameter of the bullet, to the case mouth, is the throat length.

Having a good idea of your chamber's over-all length is 'a good thing'. Nonetheless, I'd still suggest that you simply load up some 125s and just 'have at it'. As I said above, you may very well find that your rifle "likes" 125s, and shoots them like 'lasers'.

If you need to, you most certainly can load them "out" a bit. I assure you that a seating depth of 2/3rds of a caliber - 0.67 * 0.323" = 0.216" is sufficent even for hunting. If your chamber allows that long of a cartridge OAL. You DO NOT want to load a cartridge too long and jam the bullet into the lands! Pressures will go dangerously HIGH!

You MAY find that your chamber(s) are not "long" like most milsurp rifles are. That would probably be a "good" thing for shooting the 125s.

Knowing your chamber dimensions - best determined by chamber casting - is a real help in reloading precise-shooting cartridges.

Paul

gitano
10-08-2008, 10:03 PM
Y'know... if yous guys in OZ are so hot to shoot LFCs in 8mm, there might be a market for an 8mm sabot with a 7mm cavity. You could then shoot 115-grain (or even lighter) 7mm HPs. :hat: That would be an awesome roo/goat/pig combo that wouldn't pass through.

Heck, you could make an 8mm sabot with a .257 cavity. Yeehaa!!! I'd bet you could get a 85-grain .257 doing 3500 at least from a x57 case. :jumpingsmiley:

Maybe I should get some 8mm/7mm and 8mm/257 sabots made up and send them to OZ??? Since I'm pipe-dreamin' here, might as well go all the way to .22. There'd be some... "body" that'd probably buy them.

Paul

PS - Some "quick-and-dirty" calculations with QuckLoad gets an 85-grain bullet doing 3836 f/s out of an 8x57 case in a 24" barrel using AD AR2219. :D

Jorge in Oz
10-09-2008, 05:32 PM
I like your thinking Paul, you definitely have a customer in me if you made the sabots.

Also thank you for explanation and directions.

I will load up some ammo with 125 grainers and see how I go.

Cheers

Jorge

kombi1976
10-09-2008, 11:22 PM
I look forward to seeing your progress with the 125gr pills, Jorge.

gitano
10-10-2008, 01:15 PM
For those interested in 125-grain 8mm bullets...

I just got off the phone with Hornady, nad was told that they are no longer manufacturing their 125s. The fellow I spoke with expressed some dismay at that when I asked him to check. He said he owned a few 8mms, liked the 125, and that as far as he had seen, "Sales were good." Nonetheless, "officially", Hornady isn't making any more, AND they have none in stock according to this fellow.

So...

1) Buy what you can (I got mine from Graf's) as they are "gone" from Hornady's inventory, and

2) Write Hornady at https://www.hornady.com/contact_us.php and let them know that there is still a legitimate (commercial) interest in 8mm 125s. Especially you folks in OZ.

In the mean time, I'm working on getting some 8mm sabots manufactured. :D

Paul

PS - I sent Hornady hte following message...

I spoke with a fellow (Hornady employee at this phone number) today that tells me that 'you' aren't manufacturing 125-grain 8mm (.323) bullets anymore. Your item number 3230. He and I both were disappointed to hear that. I have no idea how sales are going for that product, but he said sales were "good".

I'm sure you'll say quite the contrary, but regardless of your protestations to the contrary, there is considerable interest in those bullets - especially in Australia, (I am told) where they have many 8mm weapons, AND yet not as many of the large-sized critters we have here in North America. As a result, they like to shoot light-for-caliber bullets that have a greater probability of remaining inside a kangaroo, or goat, or feral pig, or...

Please reconsider making these bullets, at least on a once-a-year special run basis.

Thanks,
Paul

tex
03-14-2009, 02:19 AM
i tried 125 and 150 in my 1904/39 and they were all rubbish. 175 gr are the go infront or 2208.