Belted VS Non-Belted
What is the current thinking in regard to a belted case, versus a non-belted case in the accuracy department only. All other things being equal, bbl. quality, action quality, bedding etc. etc. Secondly, again for accuracy purposes only (cost not being an issue), consider the following cartridges only. Which would you pick, and why for a semi-serious (non-competition) bench-gun? .300WSM., .300 WIN. Mag., .300 Dakota? THX HAWKSHAW
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I am wondering what the real difference between belted and non belted rounds. I have a large weatherby collection and I have a co-worker that says his ackley's are the way to go because the weatherby's are not as accurate. I have Lazzeroni's also and the weatherby's are just as accurate I am not sure please give me all of the in's and out's of this topic. Thanks. 0 -
Every rifle is a beast unto itself. As far as handloading goes, I personally have to put a lot more work into getting weatherby crtgs up to the best I can wring out of them. Belted Vs Non hmmm I am getting some great accuracy out of some ultramag crtgs based off of the beltless 404 jeffries. I also have a particular 7rem mag that is getting some amazing accuracy and another that I continually seem to be trying to improve.
When it comes to factory crtgs I have no idea0 -
Depends more on how well it is chambered and the barrel.
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DeBoer,
This can be a quite lengthy topic, and I hope other's like Nononsense, JustC, and Sandwarrior chime in too.
The main difference in intentions, is that the belted cases were intended to headspace off from the belt, much like a timmed cartridge. The non-belted cases headspace off from the shoulder.
When lining up the case from end to end with the barrel, the longer the distance from the bolt face to the point of headspace, theoretically, the greater the accuracy you will achieve. This is because theoretically, because the distance from the shoulder to the bolt face is longer than the distance from the front of the belt, to the bolt face. This in turn gives one less TIR, or Total Internal Runout, in engineering, and machinists' terms.
However, those savvy in reloading, and high end accuracy, can equalize that equation, by not full length resizing the case. We only partially ful length size the case, by stopping short of the shoulder, use a neck die, or a bushing die, instead of full length resizing. By doing this, it leaves the shoulder in place, where it perfectly fits the chamber. This method can also be used on non-belted cases. With the assumption that the chamber, and throat are perfectly concentric with the bore, a perfectly fit to the chamber case should have close to ZERO TIR, meaning the case should be perfectly aligned with the bore.
That said, I have a 7mm Rem Mag, and a 300 Win Mag, that I load only using neck dies. These are standard production rifles from Ruger, and Browning respectively. I say standard, but they have been pillar bedded, and a trigger job done. They will shoot well inside 1 MOA, out to 600 yards, with the loads they like. They are not bench rest guns, but seem to be at the top of their class.
Best0 -
When you speak of accuracy, you have to remember that at least 20 variables go into improving accuracy. There is no magic brand of rifle, ammo, caliber, bullet, powder etc that gives magic accuracy. Each component must be perfected to eliminate as many variables as possible to achieve best accuracy. About half the variables are in the gun and half are in the reloaded ammo (not to mention the shooter factor). Some are easier to work with than others. By spending the time learning techniques, using premium components and reloading tools and careful attention to details, very accurate ammo can be made. The same goes for improving a rifle's capabilities. Nothing in belted-non belted cases adds much to accuracy. I have achieved 1/4 MOA from 6 different calibers from .17 to .308 from 6 different manufacturers. 0 -
The .400/375H&H is one of the first belted rounds, dating from about 1905. It could be that due to the taper and very small shoulder of the .400/375 H&H case the belt was designed to give the cartridge a more positive headspace. According to Catridges of the World, this was about equal to a .358 Win in power.
Later in 1912, the .375 H&H and .375 H&H Flanged (rimmed) came along. The .375 H&H (belted) also had a small shoulder and lots of taper, so the belt was probably retained for the headspace issues. (Along the same lines, the .300 H&H, which came along in about 1925, has an extreme taper and long sloping shoulders when compared to more modern rounds. These factors on the .300 makes a belt for proper headspace pretty much a must.)0 -
The history of the belted cartridge is well known so let me make a manufacturing observation. The belted cartridges headspace on the belt and this has been a boon to production rifle makers. Go/nogo gauges are interchangable between the various calibers, makers and such. My go/nogo set works for my 338winmag as well as it does for a 375H&H. A one gauge fits all makes life in the manufacturing enviroment much easier. From the owner/shooter point of view, IMO, belt/nobelt is a non issue. If you want a rifle in a given cartridge then get the one you want irreguardless. 0 -
DeBoer,
The only 'real' difference between the two is how they headspace. The non-belted cases use either the datum diameter on the shoulder or the rim for a headspace feature. The belt is the headspace feature for belted cases, obviously. The exception to the belted case headspace is when the knowledgeable reloader resizes just enough so as not to push the shoulder back so he can use the shoulder for that feature as well.
Since we don't have any significant details regarding your rifles, we have to use some generalities to maybe cast some light on your friend's comments.
Longer freebore (or leade)
It's been somewhat of a drawback in the Weatherby chambers. The bullet 'jumps' to the lands and can be the cause of some of the inaccuracy noted by gun writers and internet experts. However, there are occasions where many of us reload with an intentional jump to the lands and still manage to have superb accuracy. I think it's more of the entire chamber being a problem than limiting the blame to the leade.
Oversize chambers and maximum headspace
Weatherby rifles are manufactured for the hunter not the target shooter. These cases have the double radius shoulder, a belt, larger diameters and longer OALs. The magazine length will dictate the OAL, not the chamber. They have to feed first time every time for the hunter under extremely variable conditions. This usually dictates a generous chamber. Generous chambers are not known for accuracy but can be worked with in order to gain as much as possible through reloading and avoiding over-resizing the case. If you maintain the hunter style rifle then you need to check every reloaded cartridge by running it through the magazine before a trip.
Now that we've gotten that out of the way, we can say that even given some discrepancies with belted case chambers, the belted cases have been recognized in many target shooting venues for their capabilities of winning. The belted cases stand side-by-side with all of the 'modern' beltless cases with equal performance. The difference is that the chambers are cut with reamers properly designed for single shot competitions not hunting.
Your friend's assertion that the Ackley cases are more accurate can be erased by the fact that their have never been many factory delivered with Ackley chambers outside of the in-house custom shops. So his statement comparing the custom barreled Ackley chambers to your factory cut Weatherby chambers is inaccurate or inappropriate at the very least.
I shoot rifles chambered for most of the Weatherby line starting with the .224 WBY up to the .460 WBY. Some are hunting rifles, others are Competition rifles. I don't have any problems with accuracy from either type.
Best.0 -
DeBoer,
What I've found over some time of reloading a lot with many different rifles is that it really boils down to the quality of the chamber and barrel. Along with the trueness of the action, of course.
As stated above the rimless/beltless case headspaces off the shoulder, the belted case off the belt and the rimmed case off the rim.
My supposition was always that since the forward part of the belted case is 'floated', sort of, that it wasn't as accurate as a shoulder head-spaced case. Well it really boils down the accuracy of the point (datum) of headspace to the bore. And how the bullet is guided into that bore. I found out with a Weatherby .257 I once owned that when done correctly, Weatherby's can be fantasticly accurate. And although I still had slightly better luck with neck sizing and therefore headspacing off the shoulder, that belted non-radiused type cartridges were still phenominally accurate. Pretty much sub-MOA vs. sub MOA when it came to comparing shoulder headspacing (neck resizing) and belt headspacing (full length resizing). Just that in my experience neck sizing produced .5 moa groups and fl sizing produce .7 MOA groups. Both can win you a contest if you stay up with the rifle.
One of the best examples of a super accurate rimmed case is the 7-30 Waters. When the chamber is concentric with the bore. When that happens, any 'float' the front of that case has while sitting in that bore is taken up as ignition occurs in that case.
IMO, though the most accurate is the cases that headspace off the shoulder. In a very true chamber, those cases easily remain the most concentric with the chamber.
Then we get to the Ackley's. What P.O. Ackley pretty much did if you haven't read up on him, is blow the shoulders forward to 40 deg. and then out to where the case body is almost straight. The first gives an excellent datum reference to headspace off of. And, as I noted above, the 'float' is taken out of where or what the case wants to do after the first firing or so. The Ackley cases give the flattest datum to headspace off of. There-fore IMO, the easiest to copy and give full accuracy from.
ADDED: Regarding the Ackley cases. All too often people take the Ackley cases, or any improved case, and try to push them as hard as they can. Ackley promoted this kind of thinking with improving the cartridges in the first place. The Biggest thing that was found out though was that even though you get a slight improvement in velocity performance, your case tends to remain closer to it's original size. It's the case life that gets extended and therefore you get the inherent accuracy from using cases that don't change much. Load Ackley's for accuracy and not speed and you will see what I mean.
-Hope that helps0
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