Is it just me that thinks that the comments about certain cartridges about which some people can't resist suggesting "long throat them" seems silly???

I've seen it in nearly every discussion of the 260Rem and several other cartridges.

People suggesting "throat them long, so you can seat them long so the bullet doesn't occupy propellant space".

Then I look in the loading manual and see NONE of the six fastest loadings REACH let alone exceed 85% of case capacity making the "problem"
from a deep seated bullet intruding on propellant space simply a non-issue.

While if the chamber is "long throated" as is frequently recommended doing, you then MUST seat the bullets out and this can easily create issues with magazine length and almost certainly cause issues with shooting the lighter bullets for caliber...

IOW if you long throat a 260Rem so you can "seat out" 140's you'll probably have excessive jump with 100's...

So in specifically throating to accomodate seated out long bullets (normally a non-issue)
you create an issue that you can't fix, because of the old saw, it's easy to take metal away, it's difficult to put it back....

AllanD

Allan

I think you're both right and wrong. Because it all depends. There are some instances where it is foolish to talk about long throating and long seating because the cartridge/bullet/rifle/magazine combination just doesn't lend itself to anything but factory type cartridges. But there are also instances where it's easy to make a strong case for long throating/seating. For example. I have a pre-64 Winchester Model 70 in 257 Roberts. With the factory throat and magazine it was a mediocre combination at best. But remove the plate from the magazine, lengthen the throat, seat the bullets out where they belong and the cartridge and ballistics take on a whole new light.

Ray

I think it's more a case of the bullet getting space for a running start into the rifling. I had high pressure signs in a load of 4350 in a 6mm wildcat, when the bullet was seated into the lands. Then I tried seating the bullet .020" deeper, and the same load was fine, no cratered and flat primers. Weird, less air space, lower pressure. I think it's the old physics thing about static friction being higher than moving friction.

Isn't there a rule of thumb specifying that for so many % increase in available powder volume, expect so many % increase in velocity?? I forget the exact numbers, but it is not particularly skewed towards long seating bullts.

That said, a friend of mine is easily a better and more experienced handloader than I am, and regularly uses long seating as one of his tricks to obtain velocities I could never even dream of - all in good safety and with long case life.

I'm not sure what to believe, except that if you choose to long throat, you'd better make sure the rifle likes the bullet weight you throated for, and not a much shorter and lighter bullet...

- mike

quote:

% increase in available powder volume, expect so many % increase in velocity

Normally 4% powder to 1% velocity. Setting the bullet out as far as possible and still function will gain you the maximum net capacity. If you are going for maximum velocity from your case it will help but the gain will normally be very small.

What I was talking about was NOT in dealing with an exsisting chamber in an exsisting rifle.

I'm talking about INTENTIONALLY making the throat Long on a newly assembled custom rifle, or atleast a custom barrel...

Cheechako,
the case you mention where the factory throat was too long
is most definatly not what I was talking about, but I'll comment I had a remington varminter in 6mmRem, that had a long throat, apparrently to accomodate the 105gr semi-spitzers that were popular in the early 60's...

Seating 70gr Noslers out for best accuracy produced loaded rounds that were 0.060" too long to fit in the shortaction magazine, so I sold the rifle
Any shorter seating depth wouldn't shoot for shit...

My issue with some chamberings, like for example the 6.5x55, is with the throating length.... trying to minimize bullet jump with shorter bullets is all but impossible, because you run out of bullet shank on the lighter bullets....
And that L O N G throat even on the american produced rifles chambered for that cartridge follow the throating originally used with the 160gr RN bullets that were originally used in the earliest version of the cartridge...

That long throat is probably detrimental to accuracy with 140's, but god forbid you say that in public....

Granted with a 140gr bulllet you CAN get a 260rem to 105%, but at SAAMI max OAL and then only with H1000 powder, but what magical thing is going to happen being able to load longer?
And in what rifle will you do it because anything longer than 2.8" simply isn't going to fit in a short action, So I'm wondering what it is I'm missing, or is it that some of my fellow shooters and loaders are simply divorced from logic?

Basically what I'm asking is; How do you reconcile irrefutable logic that is mutually contradictory?

quote:

Originally posted by Allan DeGroot:Cheechako,
the case you mention where the factory throat was too long
is most definatly not what I was talking about,

Allan

I guess I wasn't clear enough. I should have said that the throat was recut to accomodate cartridges with the bullet seated out where they belonged. This was a common improvement for 257 Roberts rifles in the 1960s and 1970s. Add the Ackley Improved case to the mixture and you had one of the most versitile combinations known. Ackley hisself thought the 257 AI was one of his better creations and Col. Whelan thought the 257 Roberts was one of the best all around rifles for North American game. All possible by the simple expediant of a longer throat and a longer magazine.

Ray

quote:

Originally posted by Allan DeGroot:

I've seen it in nearly every discussion of the 260Rem and several other cartridges.

People suggesting "throat them long, so you can seat them long so the bullet doesn't occupy propellant space".


AllanD

I recall reading an article on the 6.5x55, and factory guns... some makers used a commerical throat and lead, while others used the military setup...

Recall that the 6.5 uses LONG bullets..

IIRC, the winchester fwt was a "short" throat and could not be loaded up nearly as hot as a milsurp...

If you have the mag length and throat length, you can gain ALOT of capacity... more than most of the ackley improved rounds, in fact.


"excessive jump" is a judgement call... EVERY , and I repeat EVERY factory 257 roberts, loaded with factory bullets, to factory COAL has a HUGE HUGE HUGE jump.... but if you seat the bullets out to where they are .0275 off the lands, you are WAY past 2.8...

barnes bullets LIKE .065 or more... and the more jump the better they seem to shoot.

jeffe

Hey Allen -

I hear where you are coming from in respect of some cartridges where one may commonly use both short and/or long bullets.

With others, the long throat is the only way to go for me. Paul Marquart built me a Ruger No. 1 for the original 6.5 Mannlicher (Rimmed) case, and it is intentionally throated to handle primarily 160 gr. Hornady Inter-Lock RN bullets.

With those l-o-o-o-n-g bullets and 36.5 grs. of Tu5000 it will shoot ragged one-hole 3-shot groups at 100 yards. But, it will also shoot very small groups with both 139's and 150's of various makes...about 3/8" commonly, if I hold my tongue right. I do not want that sort of cartridge for 120's, so frankly have never tried them...wouldn't use them for my purposes regardless how well they shot.

(BTW, I don't like 3-shot groups either, but since this is a VERY pencil-light & skinny 28" Hart barrel on a stalking rifle, I have never tried 5-shot groups from this particular rifle...figger the heat of 5-shots is bound to do something I don't want....and I have never gotten 5 shots at an animal on a stalk.)

Anyway, in a .260 Rem, I'd agree with you. But for a classic 7x57 built for the 175 gr. bullets, I'd throat it long. That may make the lightest 7m/m bullets less useful in it, but light bullets are not what I would see the 7x57 as being primo for in my shooting realm anyway.

Another thing to consider, of course, is just how long a case-neck is provided by the chambering you are throating . A long case neck gives a person a lot more leeway in seating different bullet weights, and throat length may become less limiting with either heavy or light bullets.

Good thought-provoking thread, though.....

If the longest bullet for a given caliber is seated no deeper than the shoulder neck junction than #1 the magazine must be long enough to accomodate it and #2 the throating must accomodate it also. I may be mistaken but wasn't the Carcano brought out about 1891? Now that was an intelligent rifle to accomodate cartridge design. I think the 99 Savage started a lot of the short necked handicaped cartridge design. our sad military ordanance people just happened to copy it 50 years later.Oh well!

The trouble is someone thought the short bolt actions would be a neat marketing feature and than said let's see what we can stuff into them. Well they stuffed it all right.

This appears to be a very opinionated topic, Allan, and like ass holes everyone has an opinion. roger

Ok, let me further clarify.

the issue where some asshole of an engineer, or more likely an asshole of a marketing exec insists on stuffing a 257Roberts, a 6.5x55Swede a 6mmRem, etc into a 308 length action... that's gonna cause trouble.... and isn't what I'm talking about.

The typical military Mauser action designed around the 8x57 is really only, what? 5mm shorter than a springfield/Winchester/remington
long action is? yet manufactures put on their dunce caps and chamber the 257Rob and the 6mmRem both ?x57 cartridges into 7.62x51 length actions.... then add insult to injury by "long throating" them.

Yet people will go out of their way to do the same thing on custom built rifles....


What is the reasoning behind keeping the bullet base level with the bottom of the case neck?
In most cases with most propellants, particularly the propellants that are "happy" with a given cartridge and bullet weight... a bit of bullet protrusion into the powder space has little or no effect on propellant capacity...
my thought was that (like in most cases if your pet load winds up being 89-92% of propellant capacity you don't need to worry about it.
If OTOH your pet load winds up at 108% you've got a problem but you can always throat the rifle deeper after you've discovered that fact...

as for the heavier bullets in say... the 6.5x55 I remain unconvinced that there is any difference in killing power between say.... a 125gr partition and a 140gr partition. atleast not on anything I'd shoot at with my 6.5x55.


And just between you and me if I had a 7x57 I'd load it with 140's, because if I need to launch 175's I'll do it with a 30caliber. I won't even load 175's in my 7mmMag, so I can't imagine doing it in a 7x57.

I suppose that the issue I'm really "sneaking up on" is to wonder why everyone wants a particular rifle to have the broadest capability
possible, which I'm inclined to call "swiss army knife complex", yeah you can make it "capable" but it isn't "ideal" for any of the capable purposes.... as if they are worried that the specific rifle/cartridge being discussed at any given moment might suddenly become their ONLY rifle...


AllanD

Well Allan, you've lost me. I thought I knew what your initial question was but now I have absolutely no idea what the hell you are talking about.

Ray

quote:

Originally posted by Cheechako:
Well Allan, you've lost me. I thought I knew what your initial question was but now I have absolutely no idea what the hell you are talking about. Ray

I can well believe you, Ray, but then that is his opinion what ever it is. Oh! by the way, Allan, I buy into a lot of what you have to say but on some things our opinions do differ; probably caused by heredity or envionment. roger

quote:

as for the heavier bullets in say... the 6.5x55 I remain unconvinced that there is any difference in killing power between say.... a 125gr partition and a 140gr partition. at least not on anything I'd shoot at with my 6.5x55.


And just between you and me if I had a 7x57 I'd load it with 140's, because if I need to launch 175's I'll do it with a 30caliber. I won't even load 175's in my 7mmMag, so I can't imagine doing it in a 7x57. AllanD

Alan, I believe you would...and for your gun a deep throat would not be necessary. But some of us prefer to use heavy, smaller diameter bullets at moderate velocities for some of our specific applications. For us, longer throats are useful.


For me, I tend to use heavy bullets of conventional design at relatively moderate velocity in my "all around" and "medium range" rifles. In my "long range" rifles, I tend to use lighter, more streamlined, premium bullets at higher velocities.

As to convincing you of why we want to use those heavy bullets, we don't need to do that. It is enough that we want to do it. Our rifles, our choice(s). With my 6.5 Mannlicher, I do it because it is a classic load for that cartridge and I like hunting with the old classics. In my 6.5x55 I use somewhat lighter bullets...because that is what that rifle is more accurate with.

As for 7 Mags, I have several of them but find little use for them in most of my hunting. About the biggest 7 millimeter cartridge I use is the 7x65-R. And guess what?... in it I use the heaviest bullet RWS can provide. Why? It works well, shoots flat enough for every purpose I have put it to, and I like it. (Besides I can always get 20 or even 100 yards closer if I need to. I'm long ago retired. I have the rest of my life to hunt.) :<

I

Heavy bullets have high SD and make exit wounds.. good enough for me

quote:

Originally posted by Cheechako:
Allan

For example. I have a pre-64 Winchester Model 70 in 257 Roberts. With the factory throat and magazine it was a mediocre combination at best. But remove the plate from the magazine, lengthen the throat, seat the bullets out where they belong and the cartridge and ballistics take on a whole new light.Ray

Great example! roger Sadly there are few long heavy bullets in 25 cal. and no barrels designed and commercially used that will handle them.