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 -
My vote goes for non belted #1 I don't like the fact that head space is very small area of brass on a belted case compared to the shoulder on a none belted case #2 I think the case the same diameter as the case head or even a rebated rim allows for a shorter case to hold the same amount of powder & it seems the latest thinking is Shorter and Fatter is better. I however would also like to see some of the other more versed opinions. as many on this sight have opinions backed up with facts from many years of rifle cartridge testing. 0 -
the belt was developed for the H&H taper which was quite sharp with a very shallow shoulder angle. The belt was a necessity to headspace the round. The reason is still exists is IMHO some nostalgia mixed with the fact that the newer designs were easilf formed out of the old H&H brass when they were becoming factory rounds back in the 50's, 60's etc. The current belted magnums from Remington/Winchester/Weatherby etc headspace on the shoulder much more readily with much less body taper as well as sharper shoulders. A neck sized belted mag will securely headspace on the shoulder.
The "new" breed are made off of the age old 404jeffries and 416rigby as well as some wildcat takeoff's from those parent cases. These were a step larger in body dia and had no belt. By necking them down and changing some shoulder angles,..the RUM's and WSM's as well as RSAUM's were born.
I would be doing some serious research to determine between the WSM and the win mag. Both are tried and true in longrange and have pretty much equally available brss, with the edge going to the win mag. The dakota I havn't reaaly seen on the line, but then I am not at every match,..far from it these days with the youngens.
Now, for some longer range, the WSM will give up some to the larger case capacity of the win mag, making it better with slow powders abd heavy-for-caliber pills.
Lately I have heard of some very high quality brass being made for the WSM's (IIRC), which would leave only the distance to be the deciding factor. If you wan't 1000yds and informal bench work,..either will work fine.0 -
Hawkshaw,
As JustC noted the reason for the belt was pretty much the H&H cases that were used in Africa. The issue there was extraction not accuracy. While in some cases the .300 WM and 7mm Rem Mag are noted for accuracy I do believe that either shoots better when headspaced off the shoulder and NOT the belt. Good accuracy is obtained while shooting them headspaced of the belt. But great accuracy is obtained when they headspace off the shoulder. You also get much more case life out of them while headspacing off the shoulder instead of sizing the case body all the way down. My .300 WM (Armalite Ar-30) shot MOA off the belt. It shot .3-.5 MOA off the shoulder.
For me it's an easy answer. When resizing take it down only to where it headspaces off the shoulder. Plain and simple that is more accurate and follows a lot of the thinking of better accuracy of today. As well you extend your case life which leads to accuracy.0 -
Thanks Guys
Follow up!!! I've been handloading since the mid 50's, but a comment made, I would like to verify. If you are resizing a fired (belted) case, and only resizing the neck, are you sugesting that that case will now headspace on the shoulder, rather than the belt? Or would it be a combination of both, in that specific chamber? I also heard of a senario whereby a .300 win mag chamber, had the shoulder directly in front of the belt cut deeper (I assume by a few thousandts) into the chamber thereby making the case headspace on the shoulder. Comments? I'm trying to envision the down side to doing that. What happens when firing a NEW case, or factory ammo? Mabey a self applied derma-peel??? THX HAWKSHAW0 -
The shoulder will not be set-back if only neck sizing,..therefore it has been fireformed to YOUR chamber. If you only change the neck dimension, the case will headspace on the shoulder, and possibly the belt as well, to some extent.
Now, if in your second question, you meant the shoulder of the chamber was cut a little LESS deep by a few .001"s, then that would in effect create the same situation. This would allow a tighter fit and more positive headspacing using factory ammo that tends to be slightly smaller than SAAMI spec, and factory chambers tend to be a bit on the generous side in dimension.0 -
JustC---THX---Follow up. NO, on the second part. I'm talking about the shoulder at the rear of the chamber where the belt on the cartridge would normally seat. Move that shoulder foreward, such that the cartridge would move foreward in the chamber untill the cartridge shoulder would create the seal before the belt on the cartridge would seal. Effectively, transfering the head space from the belt, to the shoulder of the cartridge. THX Again All HAWKSHAW 0 -
Hawk,..the deepening of the belt shoulder in the chamber itself (larger area for belt to seat) in front of the belt, would advance the undersized factory round to headspace on the shoulder,...that is correct. however, the body in front of the belt would now be exposed to an area that upon firing, and under pressure, that would create more stretch room for that portion of the case body/web, and I would fear that that would lessen the life of the case and cause faster case-head seperation after repeated sizings and firings.
I would also suspect that as the case would then move foreward more in the chamber to headpsace, and unless care was taken to not cut the locking lug recesses in the action as deep, so that the boltface would also be more fwd, then you would have primers trying to back out under ignition due to the casehead moving away from the boltface as it progressed into the chamber deeper. That would be remedied by not cutting the lug recesses as deep, but care would have to be taken during action manufacturing to make up the difference. MHO0 -
Hawkshaw,
That is a whole lot of work just to get the first set of rounds not headspace on the belt. And, FWIW, not incredibly productive IMO. The first time fired cases aren't going to be fireformed in your chamnber anyway so the greatest increase in accuracy potential isn't there to start with.
As JustC noted you would have to set the barrel back to where it hit the shoulder, then take out from around the base of the chamber, the distance that the belt would normally be. I would then assume that if you started with good brass then you would have some accuracy increase. If you plan to cycle through a lot of brass this may be the way to go. As I would hate to 100's or so pieces of brass through the barrel just to fireform them and only get decent accuracy.
The life expectancy can be doubled on the belted magnums if you tone down your load and neck-size only. I had some 12 reloads on one set of brass and had not yet decided to toss them yet. I only burned through 40 pieces. I still got MOA accuracy with the rifle. For all the reloads, accuracy went to .3-.5 MOA
Anyway's I think that's what you're going to have to decide about. How much brass do you plan to cycle through first time. If it's a lot then go the cut-out route. If not, just fireform small lots and call it good.
-good luck0
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