Long action chamber in short caliber , good and bad ??!!

Case in point, I run a short action 308 for fclass.

Any target shooter worth his salt knows that best accuracy is achieved with heavy VLD bullets seated with the bearing surface seated forward of the donut at the neck to shoulder junction... So the OPs question is centered on this point.

Take the cartridge of your choice and the heaviest bullet you would ever want to shoot... Figure how long that loaded round would be with the bullet seated ahead of the donut. That's the round dimension you want to work with. You'll want a mag long enough to feed it and an action long enough to eject the live round. This point may seem obvious but its actually a big problem for target shooters.

Rounds like the 22BR will often have long throat's which allow the cartridge to be used effectively with heavy bullets. By Contrast the 223 or 224 Valk is typically quite short in the throat, which creates problems for guys who want to run heavy VLDs. Functionally a good functional throat length is exploited in one but not the other unless you have the throat cut longer for the 223.

My 308 SA fclass gun cannot feed a heavy round from a mag and I cannot eject a live round without pulling the bolt. Functionality would have been improved if I had built the gun on a long action.

Having said all that, this is only a problem because the throat in my chamber is long enough for me to seat the bullets that long.

So this is the problem where manufacturers design rifles to suit SAMMI spec, but the SAMMI spec is not necessarily representative of the ideal configuration of the cartridge for long range purposes.

Once you get outside the box, you need to get creative to make sure it all works as intended.
 
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Biologist said:
One reason is to be able to magazine load longer seated bullets than the limit imposed by standard .308 SA mags. The old concept of "short action" is being challenged by some of the new super-long high-BC bullets in the various 6.5 SA calibers, which are impossible to seat properly to load in a standard SA magazine that is limited to about 2.870". They have to be single fed only, which is fine for bench work at the range, and for single feed disciplines, but which eliminates possibility to use them in repeater-type disciplines like PRS matches that must feed from the magazine. Hence the consideration of LA actions for so-called SA cartridges.

I just dropped my Tikka T3X .260 Rem (short action) into an MDT XRS SA Tikka footprint chassis. Tikka T3/T3X in MDT chassis can use MDT's AICS pattern steel magazines with no binder plate, which allows for cartridge max OAL of 2.960" (which is longer than the standard SA 2.870" max mag length). The Tikka's feed ramp overhang is very small, so the no binder plate version works no problem, and is fantastic!

In my Tikka's factory stock with its "M" SA magazine that it came with, I would have to single feed all my longer seated .260 rounds that were longer than standard SA magazine length. That was OK for bench shooting at the range, as I always single feed at the range anyway. I like to seat 136gr Scenars to about 2.912", which is longer than standard SA mag length. This is now no problem for loading into the MDT no binder plate steel AICS pattern mags, and with room to spare (and I can still single feed). So I am now set up for PRS style matches with my Tikka in the XRS (if I can ever get to one, I live about 1000km away from the closest matches!).

2.960" is probably not long enough to seat for the longer heavier Berger 6.5 bullets (e.g. 156gr, 153.5gr, 144gr), but I don't plan on using those in my .260.

I never could find the Tikka "M+" mags (which can handle longer seated bullets, and which I am guessing were made for the 6.5x55 Swed) for sale anywhere (sold out), and I emailed Stoeger Canada for help on this. As usual, Stoeger was no help, would not sell me a M+ mag, would not order me an M+ mag, did squat. (Stoeger don't seem to want to learn about customer service with my Sako and Tikka rifle parts, but I digress....)

The Tikka T3/T3X fans here all know that with the standard .308 size bolt face, it is easily converted between short and long action with the bolt stop swap (Yo Dave sells Tikka SA and LA bolt stops), and a Tikka SA, MA (M+), LA magazine swap in the Tikka factory stock. With an aftermarket stock/chassis, you are stuck with what the bottom metal allows for mags.

Anyways, the Tikka T3/T3X action is a very versatile system for shooting SA, MA, and LA standard bolt face cartridges.
Click to expand...

I run an M+ mag in my t3x 260. I got it from Reliable gun, show one in stock right now. Listed as for a 6.5 creed.
 
Biologist said:
One reason is to be able to magazine load longer seated bullets than the limit imposed by standard .308 SA mags. The old concept of "short action" is being challenged by some of the new super-long high-BC bullets in the various 6.5 SA calibers, which are impossible to seat properly to load in a standard SA magazine that is limited to about 2.870". They have to be single fed only, which is fine for bench work at the range, and for single feed disciplines, but which eliminates possibility to use them in repeater-type disciplines like PRS matches that must feed from the magazine. Hence the consideration of LA actions for so-called SA cartridges.

I just dropped my Tikka T3X .260 Rem (short action) into an MDT XRS SA Tikka footprint chassis. Tikka T3/T3X in MDT chassis can use MDT's AICS pattern steel magazines with no binder plate, which allows for cartridge max OAL of 2.960" (which is longer than the standard SA 2.870" max mag length). The Tikka's feed ramp overhang is very small, so the no binder plate version works no problem, and is fantastic!

In my Tikka's factory stock with its "M" SA magazine that it came with, I would have to single feed all my longer seated .260 rounds that were longer than standard SA magazine length. That was OK for bench shooting at the range, as I always single feed at the range anyway. I like to seat 136gr Scenars to about 2.912", which is longer than standard SA mag length. This is now no problem for loading into the MDT no binder plate steel AICS pattern mags, and with room to spare (and I can still single feed). So I am now set up for PRS style matches with my Tikka in the XRS (if I can ever get to one, I live about 1000km away from the closest matches!).

2.960" is probably not long enough to seat for the longer heavier Berger 6.5 bullets (e.g. 156gr, 153.5gr, 144gr), but I don't plan on using those in my .260.

I never could find the Tikka "M+" mags (which can handle longer seated bullets, and which I am guessing were made for the 6.5x55 Swed) for sale anywhere (sold out), and I emailed Stoeger Canada for help on this. As usual, Stoeger was no help, would not sell me a M+ mag, would not order me an M+ mag, did squat. (Stoeger don't seem to want to learn about customer service with my Sako and Tikka rifle parts, but I digress....)

The Tikka T3/T3X fans here all know that with the standard .308 size bolt face, it is easily converted between short and long action with the bolt stop swap (Yo Dave sells Tikka SA and LA bolt stops), and a Tikka SA, MA (M+), LA magazine swap in the Tikka factory stock. With an aftermarket stock/chassis, you are stuck with what the bottom metal allows for mags.

Anyways, the Tikka T3/T3X action is a very versatile system for shooting SA, MA, and LA standard bolt face cartridges.
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That's why the 6.5 Creedmoor was invented...
 
For decades , the US Army's M24 sniper rifle and it's ultimate replacement both used a R700 long action even though the M24 was 7.62mm NATO . It worked just fine with the factory loaded ammo , M118 and it's derivatives .
 
HondaVTEC said:
For decades , the US Army's M24 sniper rifle and it's ultimate replacement both used a R700 long action even though the M24 was 7.62mm NATO . It worked just fine with the factory loaded ammo , M118 and it's derivatives .
Click to expand...

That's because it was originally intended to shoot 30-06 match ammo. It also fed from a blind mag instead of DBM so mags weren't an issue. It's replacement (the M2010) is in .300WM so yeah, it's a long action. Just cause the army does something, doesn't mean it's ideal, haha.
 
kthomas said:
That's why the 6.5 Creedmoor was invented...
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Yes I agree.

But now that I have my Tikka .260Rem in an XRS chassis with the no-binder-plate MDT SA mag, I can seat the bullets much longer, and the Tikka throat is long enough to allow that. Best of both worlds maybe. If I had been able to source a Tikka M+ mag, I would have been able to do that with the factory stock long ago. (Thanks Ruby76 for the heads up on M+ mag at Reliable!).

The .260 Rem has slightly more case capacity than the 6.5 CM too, so maybe can push the bullets faster for long range.

I don't know, but I suspect that is also one reason why 6.5 x 47 Lapua was invented: shorter case for ability to seat long bullets longer in standard SA mags.

Its too bad the world settled on the .308 case with relatively short fat bullets as the standard for short action. Maybe a short-sighted decision (pun intended).
The .260 Rem is the .308 case necked down to 6.5, but obviously needs more mag length and longer seating length for those beauty long range high BC 6.5 bullets.

Maybe the next big thing will be actions made in medium length and a new standard for magazine length! ;)

(...except for Tikka who already thought of that long ago).
 
The gun industry is held hostage to mags and their dimensions... but it has been a very lucrative feedback loop that even the big US manfs seem shy to break.

The XM action exists... changed anything much? not really and if shooters truly wanted or understood the benefits of a med action, the M98 Mauser in modern form would make a comeback. I don't see that happening anytime soon. Tikka is popular and does the job very well... just need more mag options.

More bullet options in smaller cals raise the LR performance bar higher then it has been in years. A host of 'short' options from 22 to 6.5 cal can easily and accurately put hits on target to 1200yds without muss or fuss. How many shooters actually shoot past 1000yds? past 500yds? heck, even 200yds?

I am now playing with a combo that will fit in an AR10 mag ... and easily plink to 1400yds.

Today, it would seem the trend to a micro action would likely garner more sales.... and make life with the Dasher a no brainer... and so far, that hasn't really gone anywhere.

YMMV

Jerry

PS.. to the OP, if you want to run a standard SA cartridge like the 308win or 284 with big long heavy bullets, a long action and suitable mags would make a nice set up.... but then, you have a host of other med and long action options that would fit as well and maybe offer more performance. Depending on what you want and like, there are solutions for pretty much any combo
 
Mystic Precision said:
The gun industry is held hostage to mags and their dimensions... but it has been a very lucrative feedback loop that even the big US manfs seem shy to break.

The XM action exists... changed anything much? not really and if shooters truly wanted or understood the benefits of a med action, the M98 Mauser in modern form would make a comeback. I don't see that happening anytime soon. Tikka is popular and does the job very well... just need more mag options.

More bullet options in smaller cals raise the LR performance bar higher then it has been in years. A host of 'short' options from 22 to 6.5 cal can easily and accurately put hits on target to 1200yds without muss or fuss. How many shooters actually shoot past 1000yds? past 500yds? heck, even 200yds?

I am now playing with a combo that will fit in an AR10 mag ... and easily plink to 1400yds.

Today, it would seem the trend to a micro action would likely garner more sales.... and make life with the Dasher a no brainer... and so far, that hasn't really gone anywhere.

YMMV

Jerry
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Borden makes a 6BR dedicated action, called the Borden Super Short 6.

However, it's very easy to make a regular short action feed a 6BR based cartridge with robust reliability. There are many mag spacer kits available that can transform a regular AICS pattern mag (or even AW) into one that reliably feeds 6BR based cartridges. MDT makes mags specific to that cartridge that perform very reliably. I've even found that ARC mags, without any modification, seem to function with 6BR based cartridges just fine. And if you get a regular SA action, you are not just limited to the BR cartridges if you eventually want to spin up a barrel for a different/more conventional cartridge. I don't see "micro actions" really going anywhere, but I've been wrong before.

As far as rifle manufacturers being held hostage to magazine dimensions - you are only held hostage to your own limits on ingenuity. There are some rifle manufacturers that are coming up with some very ingenious advancements in cartridge and rifle design.
 
HondaVTEC said:
For decades , the US Army's M24 sniper rifle and it's ultimate replacement both used a R700 long action even though the M24 was 7.62mm NATO . It worked just fine with the factory loaded ammo , M118 and it's derivatives .
Click to expand...

I am playing to build a 1960's / 1970's era Palma Rifle (7.62 NATO) with a Schultz and Larsen barrel and M1917 receiver. I found I needed to put a spacer at front of magazine - to keep the rounds to the rear - like the Isreali's did in their conversions of 8x57 to 7.62 NATO - it now feeds from magazine fine - I think is because of the feed rails milled under the receiver - want that brass starting from back there to feed properly to rise up and release for that controlled round feed, which the Remington 700 does not have. I am sure is altogether different geometry when the 7.62 NATO feeds from feed lips on a detachable mag. Opposite, my Model 70 Winchester (which was push feed) had spacer in rear of magazine for the 308 Win in that M70 Long Action. I do not know if the Army M24 system in 7.62 had a spacer in mag well or not.
 
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FYI - "Long Action" - so M1917 was made in WWI for 30-06. I have one that someone converted to 300 Weatherby Mag. There were NO alterations to the receiver mag opening or feed rails - the magazine was fabricated by removing the rear end of an original and brazing on a .050" cover onto the rear - so the modified magazine (now .050" longer at the rear) fits into an unaltered M1917 military stock. As far as I can tell, it uses an unmolested bolt stop - but, of course, bolt has to be run back hard to stop to pick up next cartridge from magazine. But a very long "Long" action, that I now have a twin feeding 7.62 NATO (or at least the Hirtenberger version of that).
 
Can't wait to see the next Rem 700 SA, AR15, 1911 or Glock compatible widget.... but maybe plastic ammo counts???

There used to be a time I couldn't wait for SHOT show info to come out.... not alot of excitement in the last many years.

But then, maybe some will take advantage of what 3D and additive manf can do????

Oh well, things don't change a whole lot in the firearms industry.... M1917s, that's a blast from my past. Did alot of shooting with these old gems.

Looking forward to the next step forward....

Jerry
 
HondaVTEC said:
Did it work ? Yes , it did .
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Of course it worked, I don't think anyone ever disputed that you could run a short action caliber in a long action. The question was what are the pros/cons of doing so. It made sense, kinda, for the US Army to build the M24 on a long action because they planned to run it as a 30-06. When it turned out that they didn't quite have the stock of 30-06 match ammo they thought they didt, they chambered them as .308s and it worked. It also worked out later on to re-chamber them (with new bolts) as a .300WM (M2010). For literally anyone other than the US Army (in the late 80s/early 90s), chambering a .308 with which you plan to only use factory/mil-spec ammo on a long action is basically retarded. The only advantage, for anyone, of running a .308 on a long action is being able to use heavy for caliber (read not 175gr) bullets. So unless your criteria for a rifle build is "I want to do what the US Army did way back when" there is zero reason to build a .308 on a long action if you only plan to shoot factory ammo.
 
Biologist said:
Yes I agree.

But now that I have my Tikka .260Rem in an XRS chassis with the no-binder-plate MDT SA mag, I can seat the bullets much longer, and the Tikka throat is long enough to allow that. Best of both worlds maybe. If I had been able to source a Tikka M+ mag, I would have been able to do that with the factory stock long ago. (Thanks Ruby76 for the heads up on M+ mag at Reliable!).

The .260 Rem has slightly more case capacity than the 6.5 CM too, so maybe can push the bullets faster for long range.

I don't know, but I suspect that is also one reason why 6.5 x 47 Lapua was invented: shorter case for ability to seat long bullets longer in standard SA mags.

Its too bad the world settled on the .308 case with relatively short fat bullets as the standard for short action. Maybe a short-sighted decision (pun intended).
The .260 Rem is the .308 case necked down to 6.5, but obviously needs more mag length and longer seating length for those beauty long range high BC 6.5 bullets.

Maybe the next big thing will be actions made in medium length and a new standard for magazine length! ;)

(...except for Tikka who already thought of that long ago).
Click to expand...

I highly doubt that medium length actions will become the next big thing in order to accommodate the .260 (they do shine with SAUM type cartridges though). The 6.5 Creedmoor basically does exactly what the .260 does but was designed from the outset to fit the current SA standard. That's also why .260 is basically a "dead" caliber, there's very little factory match ammo available for it, making it mostly a handloader's cartridge.
 
Potashminer said:
FYI - "Long Action" - so M1917 was made in WWI for 30-06. I have one that someone converted to 300 Weatherby Mag. There were NO alterations to the receiver mag opening or feed rails - the magazine was fabricated by removing the rear end of an original and brazing on a .050" cover onto the rear - so the modified magazine (now .050" longer at the rear) fits into an unaltered M1917 military stock. As far as I can tell, it uses an unmolested bolt stop - but, of course, bolt has to be run back hard to stop to pick up next cartridge from magazine. But a very long "Long" action, that I now have a twin feeding 7.62 NATO (or at least the Hirtenberger version of that).
Click to expand...

The M17 was simply the "Americanised" version of the British P14, which had been envisioned originally as a 280 (similar to the 280 Ross, who's ballistics impressed a lot of people at that time). Hence the longer action. WW1 put an end to that plan, however. I have built quite a few large magnums on those actions, from a 375 Wby to a wildcat 30-416 Rigby Improved. They are a very good action for those kind of mods, but it is a lot of work to get them right. Still, at the time, there weren't a lot of other options. Wouldn't be my first choice for a target gun, but they are certainly capable of good accuracy. - dan
 
rugbydave said:
I highly doubt that medium length actions will become the next big thing in order to accommodate the .260 (they do shine with SAUM type cartridges though). The 6.5 Creedmoor basically does exactly what the .260 does but was designed from the outset to fit the current SA standard. That's also why .260 is basically a "dead" caliber, there's very little factory match ammo available for it, making it mostly a handloader's cartridge.
Click to expand...

That's because the 6.5 CM folks haven't figured out the 260 is actually faster. More case capacity is advantageous. And if you aren't loading it for basically an AR10 mag or similar, there is no advantage to the 6.5. Works fine, either way. - dan
 
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