Rifle Action Question

[AWLEAPHART]

Hello everyone,
I have read some Articles that mentioned ( Well I can Get 2800fps with Remington 700 but I can get more out of a Bat Action.) What makes this possible? Also what about accuracy? How can one do it and the other can't?
Anthony

 

[spclark]

Accuracy is a relative thing.

Any factory action is likely to be made to "looser" tolerances than just about any custom action, such as the BAT you mention (or any of maybe 25 or 30 other reliable marques!). As such an owner's expectations about accuracy must be tempered by the tolerances his action + barrel was built to.

A stock Rem 700 will give good results if one doesn't expect to compete with custom-built and well-handled rifles.

As in many other endeavors you get what you pay for more often than not. Once you've spend the $$ to get a Rem 700 "tuned up" for reliable accuracy you may then find you'd have been better off buying a custom action in the first place.

 

[AWLEAPHART]

Well I am one of those that are bad about having a Remington all tuned up. It’s just cheaper on my end if I already have a Remington action to use verses getting a new Bat Action. I think Bat action is just about at the top when it comes to the best of the best.
But when came to Velocity and pressure signs, I didn’t think tolerances made a different to getting more speed from one action to another.
Anthony

 

[ChrisNZ]

There is no useful relationship between the make of action you use and the velocity you can expect from -sensible- loads. The brass is always the weakest link and you don't want to find those if you can avoid it..

Wringing the very last foot per second out of a case makes no sense and only kills the brass prematurely, even though any reasonable action can take the treatment

Chris-NZ

 

[Laurie]

Anthony,

I largely agree with Chris's views on this. Tightly toleranced and breeched custom actions do let people run higher pressures than many factory actions, but potentially at the expense of the brass.

At the end of the day, if you serially over-load cartridges in relation to the action strength and design, you risk having insufficient leeway if something pushes the load 'over the edge' - a new lot of powder, hotter day, or whatever - and sees the primer or much worse the case-head fail.

In the custom action with any given brass quality and condition, it is likely to happen at somewhat higher pressures, and shooters who 'push' their loads can get into trouble with either type - so no difference there. The higher risk from custom actions can come from very good actions producing fewer warning signals, in particular they often open easily on a very hot load and primers may not end up as flattened or cratered as in a factory action.

There is one aspect though that often does allow you to run legitimate higher pressures with such an action - the firing pin diameter and its fit in the bolt-face, the former small and the latter very close. This provides more support to the primer, so extrusion (cratering) and blanking (piercing where a small disk of primker metal detaches from the primer cup and is usually blown back into the bolt through the firing pin hole) at less than allowed maximum pressures are avoided. It is much more of an issue with cartridges that use small size primers than large. It is also why Greg Tannel (Gre-Tan Engineering) has built up a good business in modifying factory firing pins and bushing bolt faces.

There are many good reasons for using a custom action if you can afford it - greater safety margin, and being 'true'. Also, normally being stiffer and locking up more evenly than an out of the box factory action, they usually perform much better at maximum allowed chamber pressures. In that sense, plus the primer extrusion issue, they can legitimately allow the use of heavier loads and higher pressures. You get nothing for nothing though and you'll pay for the performance in barrel throat wear and tear.

Laurie,
York, England

 

[Laurie]

A remington action is 1.350 inches in diameter and the barrel tenon is 1.0625 inches leaving us just over a 0.250 thick receiver.
On a 2 inch bat with a 1.250 barrel tenon you have 0.750 thick receiver or 0.375 per side versus 0.125 on the Remington.The thicker tennon and bigger receiver yield less during firing so your brass doesn't work harden as quickly.This makes extraction easier.
Also the 0.062 firing pin diameter allows you to load warmer loads without piercing primers.

If you have an old military action chambered up for a more modern cartridge they will often times stretch on you.There just isn't enough metal in them.The Big BAT Action weighs over 6 pounds without a barrel,trigger,scope base or rings.
Lynn

Good points Lynn. Even worse than the Remington is the WSSM version of the Winchester M70 whose fat case and large chamber diameter + 65,000 psi PMax chamber pressures sees even thinner chamber and receiver walls around the cartridge. Throw in thick brass and a lot of case body expansion at those pressures and you get very hard extraction. I had one of these dogs a few years back - worst modern factory rifle I've owned - and before anybody says my handloads were 'too hot', I'm talking about factory ammunition which I had to buy some of as you couldn't get unfired WSSM brass in the UK for a long time. (Download the cartridge and the heavy brass doesn't obturate properly, so every fired case is thick with soot - a no-win situation!)

Your point about old military actions is well taken. Take the barrelled action out of the stock and marvel at the shallow and thin receiver side-rails on most models. I have a slight quandiary here. I have a budget .300 H&H Magnum F-Class rifle built on an old WW1 Winchester manufactured [Enfield] Pattern 1914 action from a 0.303" service rifle. It was built out of the gunsmith's old parts bin, only the Ken Farrell scope rail new. (Even the barrel was secondhand being an Australian Maddco 0.308W chambered Heavy Palma 1-12" twist job whose chamber and throat were cleaned out by the setting back and rechambering to the long .300 H&H.) It actually worked very well provided you kept pressures down to reasonable levels (190s at a little below 3,000 fps with a case-full of H4831). The Winchester cases, which are of superb quality in terms of conistency, see the belt area expand a little on each shot and become too large for the minimum SAAMI spec belt recess after only four or five firings giving hard chambering followed by the P'14's huge claw extractor pulling straight through the extractor rim.

However, I now face returning the rifle's components to the scrap bin or rebarrelling - not a cheap job in the UK, especially as it has become difficult to get examples of the cheaper match barrels here such as Pac-Nor. I have lots of heavy 0.308" match bullets on hand and am considering the .300 Rem SAUM with a 1-11" twist barrel for the old Winchester. Or ...... maybe an old favourite that German Salazar would approve of, the .30-06. (This needs an M1917 bolt swap to get the correct bolt face). Everybody I mention it to says don't be mad, rebarrelling an M1917 / P'14 military job is a 'waste of money'.

Being an awkward old cuss, I'm tempted though. It's no Barnard or BAT and never will be, but I'd love to make a point or two with a rifle built around a near 100 year old action!

Laurie,
York, England

 

[ChrisNZ]

.300 H&H huh? A peashooter!

One of the local lads has a 416 Rigby built on an opened-out P14 action Lawrie. Several of his mates have Weatherby eyebrows to prove they've fired it.

Chris-NZ

 

[Laurie]

Hi Chris - good to hear from you again.

You're absolutely right - the old P'14 action was for many years about the only off the shelf affordable action that could be used untouched for .300 Win Mag and similar, and could be gunsmithed for the bigger / fatter cartridges like the Weatherbys. In this day and age of £1,000 plus (or should that be £1,500 plus?) custom actions, it seems to have been almost entirely forgotten about here in the UK. My example is the only one I've come across in years, although there must have been many around and many still sitting in people's gun cabinets.

I think part of that is the move away from big cartridges here - .270 win and .30-06 are regarded as OTT by most British sporting shooters unless they have aspirations to go on an African shooting holiday, or maybe N. America for moose, elk and bear - in which case the Cz550 Magnum or Remington 700 in appropriate .375 or 40 cal chamberings are used. When I worked part-time in a large gunshop I saw the odd older 'African' magnum rifle pass through, but all were 'quality' examples such as cased H&Hs, custom built Mausers etc, never a P'14. The only cheaper used models I ever saw were from Brno / CZ, the old ZKK601 and modern Cz550.

So, this still leaves me with the question of whether it's financially sensible to rebarrell my rifle to a short magnum. I know it'll work and it'll almost certainly shoot well as long as loads and pressures are kept a little down. The other question is how often I would take it out. I have a Savage single-shot target action + True-Flite barrel in 6.5X47L on order to use as an alternative to my .223 Savage F/TR barrelled action in the McRees Precision modular stock, as a 'club competition' F-Open rifle - a switch-stock system rather than switch-barrel if you will. That and my former F/TR .308W Barnard-Eliseo tubegun now set up for Open will keep me going in this class for years - likely until I 'pop my clogs' as the locals here in Yorkshire say!

Such is the move to F/TR that there is now far less competition at club level in Open than in F/TR, and those who do shoot it, mostly use 6BR, .260 Rem, 6.5X47L and similar. The guys with the 6.5-284s, .284 Wins, and especially the 7WSMs don't want to use up barrel life in club comps except for the occasional load-testing or sighting-in shoot.

So, I'm still swithering. I know you can't have too many rifles, but this might just be one too many. If I can find an M1917 bolt (which shouldn't be hard as there were lots of old M1917 based 7.62mm TR rifles around until recently), I'm very tempted by .30-06, an old favourite of mine as a target cartridge. I'll blame it all on that man German Salazar, who's reinfected me with the dashed .30-06 virus! Where are you German? It's time we heard from you.

Laurie,
York, England

 

[GermanS1]

Here I am! Sorry to have had my head down for so long, I was attending to that four letter word (w..k)

As to the basic topic of the thread, I certainly agree with what Laurie has posted as well as Lynn's comments regarding action size and rigidity.

I will only add that the system includes not only the action and barrel and brass, but also the clearances between brass and barrel. Among these are the bolt to barrel clearance which inevitably leaves some portion of brass exposed (and subject to failure) but also the diametrical clearances between brass and chamber. Brass and steel are elastic, of course, but that elasticity has a limit (lower for the brass by far). Once the brass enters the plastic deformation level, extraction will always be tough as it will not spring back in the chamber, in fact, it will be nearly locked-up to the chamber walls.

That characteristic of cartridge brass is accounted for in the clearances normally used in chamber reamers and resizing dies and also acts as a pressure limiting factor along with all of those mentioned previously in this thread.

Now, on to the real important topic - Laurie, go for the .30-06! No need for a new barrel, wait until someone rebarrels a fullbore rifle and you get a good deal on his take-off (as you originally did). The one I built with a 1:13" take-off shoots wonderfully with heavier bullets (within reason) (http://riflemansjournal.blogspot.com/2010/06/ballistics-heavy-bullets-in-113-twist.html) and with the 1:12" becoming more popular, you might even stumble across one of those. Then you can talk your club into allowing it into F-TR. We allow .30-06 in F-TR in our club matches because it's no big advantage over a .308 and we have several members who use thir hunting rifles for it, no sense putting them into Open.

Excessive pressure is the handloader's biggest area of concern (or should be) and I'm glad this topic has come up as I believe it to really be worthy of attention by all of us, but especially newer reloaders. I'm amazed at how frequently I see problems which are clearly pressure related while the shooter is in denial saying something on the order of "It can't be too hot, it's the same load Joe/Jim/Jon/Betty uses. It seems our repeated warnings to start low and work up too often fall on deaf ears.

 

[AWLEAPHART]

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