Putting a "D D " ring in RCBS & NOE molds

[Wayne S]

Does anyone have or know of someone that has the ability to put "D D " rings in molds
And NO, without Walt, ect.ect.

[fatnhappy]

I believe Erik does, or did. He advertises it on his website about halfway down the page. I chuckled when I read the last line.

Need a mould hollowpointed? (http://www.hollowpointmold.com/)



Drive band enlargement of multiple bands
$25.00 setup fee per mold + $5.00 per drive band enlarged.
All work performed starting with careful measurements of castings and mold dimensions. Machining performed on a Bridgeport CNC mill with special purpose cutters. A nose band can be added to a bullet with an undersized nose to fit it to the bore.

REQUIRED: send a few unsized castings from the mold along for measurement reference.

I won't do all the bands on a Loverin design mold!

[HARRYMPOPE]

Erik Ohlen of Hollowpoint Mold Service can do it.And accurately.If you ever watched Walt do one you wondered how he ever got one right.he did it with a hand held cutter slowly closing the mold and sort of guessing at the location.

George

[Jack Stanley]

Erik did a four cavity Lyman mold for me and it is just right now . The work is first class to be sure .

Jack

[walltube]

Wayne S,
Erik O. is the way to go.

Erik cut a .301" diameter 'D' ring on an Ideal\Lyman 311334, and, enlarged the driving bands to a proper .311" diameter. Erik's stellar workmanship emphasised the glaringly poor workmanship standards of Lyman; and almost non-existant QC. You know, the usual too small diameter and\or out-of-round cavity.

I also bought a replacement pair of Erik's Allen head mould handle screws. Likewise very good.

Turn-around time was very quick and painless..:)

Y.T.,
Wt.

[Char-Gar]

That "double d" was one of Walt's brainchilds. I always thought it sounded like a good idea, but don't really know of anybody who has tried it.

Walltube.. How did that Double D work on your 311334? I have a DC mold in that number that won't cast a nose larger than .299, no matter what alloy. Might be a good project for me to try.

[walltube]

"Walltube.. How did that Double D work on your 311334? I have a DC mold in that number that won't cast a nose larger than .299, no matter what alloy. Might be a good project for me to try."
Charles,

If my formerly .299"-.297" nosed 311334 (now .301") works as well as it looks I can expect some good performance in any of my .30 caliber rifles. I cast a few to see how well they fit into the muzzle of a rarely ever fired M700 '06. Took a bit of pushing to get half the nose into the bore. Needed a pair of pliers to extract same.

Assembled a test round to experiment chambering and extraction in a 1903 Springfield. Base of boolit at neck\shoulder juncture resulted in a stuck boolit. Slight tap with cleaning rod pushed boolit out. This '03 has a new High Standard match barrell date stamped 10-44. Soft lead slugs indicated .3005" bore, .308 groove . Deeper seating is in order.
Be a week or two before I get to a range where all speculation ends.

Char., I'd say give it a go with Erik. What've you to loose?

Y.T.,
Wt.


__________________

[nanuk]

you could embed grit into the nose only, and lap the nose bigger.

[MikeS]

Excuse my ignorance, but what is a "DD" ring?

[Jack Stanley]

Mike , it's a very small band cut into the bore riding nose section to help guide it along . NEI used to cut it on some of their molds and many of the old Lyman bore ride designs can benefit from it .

Jack

[turbo1889]

Excuse my ignorance, but what is a "DD" ring?

A "DD ring" is a small band on the base of the nose ogive at or near the top of the bore riding section that engraves in the rifling and ensures that the nose of the boolit is guided and centered in the guns bore. The AM#31-216T design (a group effort between me and Tom) at Accurate Molds has three DD rings on its nose that measure 0.302" where as the main bore riding section measures 0.299". Link below:

http://www.accuratemolds.com/bullet_detail.php?bullet=31-216T-D.png

Normally, the NEI molds by Walt (who invented the concept) only had one DD ring on the nose. You can put more then one if the rings are thin enough to easily engrave in the rifling. Basically it makes the boolit usable in a wider spectrum of bore sizes (I am referring to the minor barrel diameter dimension across the lands of the rifling). For example when AM's tolerances of -0.000"/+0.0015" are taken into account the AM#31-216T boolit design with its current dimensional specs. unchanged is capable of being used in guns with minor bore diameters from 0.300" to 0.302" with most alloys with minimal accuracy problems.

For comparison for normal bore riding type boolits with a long nose the nose bore riding section diameter must match the bore diameter within -0.000" to +0.001" for hard alloy ( Alloy >= 18-BHN ) and +0.0005" to +0.0015" with medium hardness alloy (14-BHN < Alloy < 18-BHN ) to allow both easy chambering (assuming a quality throat in the barrel) and ensure the nose is properly supported to provide quality accuracy.

Basically, depending on the exact dimensions and configuration the use of a DD ring (or two or three) on a boolit design with a long bore riding nose allows the boolit design to be successfully used in a larger span of minor bore dimension variances between individual gun barrels. It usually doubles the tolerance range or more.

It can also be add to an existing boolit mold not including a DD ring in the original design to fix a bore riding section which is too small for the gun(s) in which it is being used which is the objective of the OP of this thread.

[MikeS]

Ok, thanks, I wondered what those rings were called. Don't they sometimes also put lube in them?

[Fishman]

Turbo1889 an excellent description as is usual for you. Thanks, I didn't understand the advantage until I read your post. This approach seems like it would work well in milsurp calibers like 6.5 swede and 303 Brit to name a couple where wide variations are possible. I mean, you can size the base easily enough but the nose is more difficult.

[walltube]

turbo1889's last paragraph describes exactly why I had ErikO cut a .070"w x .301" deep DD ring into my Ly. 311334 mould.

Without a 'D', this mould produced a boolit that was for all practical purposes useless for my .30 caliber rifles. There was no engagement of the bore ride to the tube's lands. It wobbled like a drunken pis ant on its way to the muzzle. The "pattern" at a 50yd. target was laughable. This humour wore thin. Of course, this particular Ly. 311334 mould, had it been cut to a NOE or A.M. standard, there would have been no need of a "D".

Fishman,
Yes! to your statement about mil-surp rifles and a "D" ring boolit.



To again quote turbo1889...
about "D" multiples and A.M.'s 31-216T; I consulted Mr. Tom about 31-216T attributes. I think this design would have been better suited to a certain No.4 Mk.I. Instead I chose 31-220B. Not a bad choice mind you, but multiple, narrow width "D" rings promise better, easier engagement of boolit nose to rifleing. Another instance of my 'thinking' :rolleyes: being a day late and a dollar short...

I often wonder what H. Guy Loverin had in mind with his multiple drive band designs. Certainly not to just accomodate loob. Eh?

Ya'll have a good Sunday at the Sooper Bowl :),
Wt.

[turbo1889]

. . . I had ErikO cut a .070"w x .301" deep DD ring into my Ly. 311334 mould.

Without a 'D', this mould produced a boolit that was for all practical purposes useless for my .30 caliber rifles. There was no engagement of the bore ride to the tube's lands. It wobbled like a drunken pis ant on its way to the muzzle. The "pattern" at a 50yd. target was laughable. This humour wore thin. Of course, this particular Ly. 311334 mould, had it been cut to a NOE or A.M. standard, there would have been no need of a "D". . . .

Your description is exactly why I now try to put a DD ring(s) into the nose of almost any bore riding nose rifle boolit I design at this point. I have experienced the exact same thing as you have many times with an undersized bore-riding boolit nose. Plain old bore riding nose rifle boolit designs without a DD ring do work very well but if and only if the diameter of the bore riding portion of the nose is just the right size for the barrel of the rifle they are being fired in. The longer the bore riding portion of the nose the more critical the fit is. And I wouldn't go so far as to say that using a DD ring design completely solves this issue. It allows a larger tolerance range but even a DD ring design can only do so much and there can still be problems if the nose diameter is too small for the barrel of the gun it is being fired in.

On a side not I would say that although you are correct about NOE, AM, MP, MM, and the unfortunately now past tense BRP molds are/were cut to much higher quality standards there is still “due diligence” required on the part of the person buying the mold. If for example you have a .303-Brit. and you just ASSume that the minor bore diameter on your guns barrel is 0.303” and order a boolit with that diameter bore riding nose section and it instead turns out that your gun really has a 0.306” minor bore diameter then things aren’t going to pan out so well. Tighter tolerances and better quality control on the part of the mold craftsman do you no good if you don’t supply the right numbers for the boolit to fit your gun. In that example situation of a 0.003” under estimate for the size ordered even a DD ring design may not perform entirely to your satisfaction because that little DD ring would be riding the bore rather then engraving in the rifling although it would probably do better then a plain old bore rider.


. . . I consulted Mr. Tom about 31-216T attributes. I think this design would have been better suited to a certain No.4 Mk.I. Instead I chose 31-220B. Not a bad choice mind you, but multiple, narrow width "D" rings promise better, easier engagement of boolit nose to rifleing. . .

The design as dimensioned currently with a 0.299” diameter bore riding nose (-0.000”/+0.0015” tolerance) and 0.302” diameter DD rings (-0.000”/+0.0015” tolerance) is intended for standard 30-cal. rifle barrels 30-06 chief among them but also including many others such as the various 300-mag and 300-wisper. Guns that would rarely have barrels with minor bore dimensions smaller then 0.2995” or larger then 0.3015” which the boolit is nearly perfectly dimensioned to fit considering Tom at AM usually hits his tolerances nearly dead center in the middle of that range he specifies.

For a No.4 Mk.I. I would highly suggest slugging the barrel and getting the critical dimensions and adjusting the nose diameter specs. accordingly. If for example after slugging the barrel I had confirmed it had a true 0.303” minor bore diameter then I would simply use the note field in the AM online order form to request that all the diameter dimensions of the nose be increased by +0.003” accordingly which would make the bore riding diameter 0.302 (-0.000”/+0.0015”) and the diameter of the DD rings on the nose 0.305” (-0.000”/+0.0015”) and knowing that Tom usually hits nearly dead center of his tolerance range and in addition having the ability to adjust those diameters slightly myself by varying the amount of tin, antimony, and arsenic in my alloy I could make the boolit fit like a glove in the gun which both you and I know although not the only consideration certainly goes a long ways towards solving the accuracy puzzle to our satisfaction.

[turbo1889]

Anymore I consider there to be six critical factors in the internal dimensions of a gun that in a perfect world the boolit design would take into account:

~ Inside neck diameter of fired case from full power jacketed bullet load (the maximum and the preferred boolit body diameter for portion of boolit inside case).
~ Throat diameter (the maximum and the preferred boolit diameter for boolit front driving band(s) forward of the case mouth).
~ Throat depth from mouth of case at whichever is smaller the throat diameter or inside neck diameter above (the maximum and the preferred front driving band(s) projection forward of the case mouth)
~ Throat taper profile from the end of the front driving band to the point where there is a full rifling profile, usually this is a constant angle taper with varying steepness of the angle but not always (how drastic the change needs to be from the “full diameter” of the front driving band(s) forward of the case mouth to the bore riding section of the boolit if a bore riding boolit is used or how quickly the nose must taper to fit in the chamber for a design that does not use a bore riding nose section)
~ Minor bore diameter of the barrel preferably measured just forward of the throat (to determine bore riding nose section diameter and DD ring diameter).
~ Major groove diameter of the barrel preferably measured just forward of the throat (a double check to be sure the boolit diameter determined from the throat diameter and/or inside neck diameter is sufficiently large enough).

Now, here is the real shocker, I put those in order of importance in my mind at this point. The one I list last of all is usually the one given first by most people and I was in that same group at one time but I now consider the throat diameter and the diameter of the inside of the neck of a fired case to be a better indicator of the correct diameter of boolit to use. The only real exception is when the major groove diameter of the barrel ends up being larger then the throat diameter or more commonly the inside neck diameter of a fired case. At that point it becomes a concern as to whether or not cast boolits can/should be used in the gun as is and if modification of the gun is necessary. So far with cast lead boolits I really haven’t run into any significant problems with using too large of a boolit based off of the throat and inside neck diameter. An excellent point in that regard was a well worn .303-Brit. which had a major groove diameter of about 0.316” in its barrel but the inside case neck and throat diameter and depth was large enough to accept an 8-mm boolit design sized to 0.324” and it shot good groups so loaded.

[walltube]

turbo1889,

Month or two ago, I visited Tom to discuss a .318" major dimension clone of Lyman's 323471. Please see A.M.'s cataloge no. 32-220B.

This I thought ought to be a dandy in my Faz No.4MkI. I entered dimensions from barrell pound slugs that indicated .315" x .304" into the Note Field. Tom counseled me to not get carried away with my wanting a .305" bore ride given difficulty in accurately measuring a five groove barrell slug. I insisted .305". Thus far the Faz is digesting this boolit rather well. Early testing at 50yd. targets are nothing to write home about, but I am in no hurry. Half the fun is getting there.

Yes! Tom's moulds deliver exactly what he advertises. WW (I think that what it was) yields .318". My rendition of Lyman's No.2 gave a reading of .319".

Thank you for your posts, good reading. Your advise is well taken. That 31-216T sho' looks good.......

Y.T.,
Wt.

[turbo1889]

I like it too (but I am a little partial after all ;) ).

In truth though I have actually had better results with the AM#31-180B which is an earlier cruder version of the same concept that was intended mainly as a "proof of concept" plain base plinker boolit that I took the critical dimensions off of a couple .303-Brit. guns, several 7.62x54R guns, and one 7.7-Jap. and kind of mish-mashed the dimensions together to come up with something I hoped would work in all of them. Ended up converting one of the two cavities of the mold to a round nose profile with some careful work with a ball end mill cutter and some lapping compound and it works in all of them and even 7.62x39 guns especially my SKS in round nose configuration (for feeding in semi-auto).

Printed this group some time ago at 300-yards with it out of scoped Nagant with a particular load combination that shoots really well out of that gun:

http://farm4.staticflickr.com/3066/5721239694_39e441cc5e_z.jpg (http://www.flickr.com/photos/54455625@N04/5721239694/)

I have yet to obtain that kind of performance at that range out of the AM#31-216T out of a modern solid 30-06 bolt gun with a nice bore and good chamber and throat. She groups real nice at the hundred yard line no problem but the groups just fall apart trying to reach out to the three hundred yard line. At least so far; I'm not through trying yet.

Overall, its not so much advise I'm trying to spread as much as it is a little outside of the box thinking. Which I cannot of course claim original credit for since Walt at NEI is the first I know of that came up with the DD ring idea and most certainly predates a young pup like me and that mold maker out of Australia beat me to the idea of just covering the nose section with little DD rings to engrave in the rifling by several years unbeknownst to me at the time I was first working on the idea with Tom at AM until someone pointed out the existing designs in the down under guys catalog with the same basic idea that had been there for several years. Which by the way is where you gen get a rifle boolit for the 7-mm cartridges that uses multiple DD rings on the nose (AM doesn't do anything smaller then 30-cal).

Oh, forgot to say, that 32-220B design looks like it would be just the ticket for a "fat-30" caliber gun with a heavily eroded throat that needs a lot of "full diameter" boolit length sticking out into the throat and less bore rider length.

[HARRYMPOPE]

Stan Borjesson of Camas Washington was the one who gave the idea to Walt . He was an early CBA experimenter and shooter and a friend/mentor of mine.The NEI 188 DD won quite a few matches back in the 1990's in he CBA on the West coast.

George

[walltube]

turbo1889,
My Faz is an OBESE .30 caliber. :) The .315" groove measurement is more a .3155". Hence my wanting a .318" dia. boolit. You are spot on with your 32-220B "ticket" thoughts. I chose this design because it satisfied what I believe to be the perfect boolit for a longish worn throat .30 caliber rifle. H.G. Loverin greatly influenced my decision. Time and testing will tell. By the way, bon't be so shy with your 31-216T and promoting out-of-the-box CB thinking. That is what makes Cast Boolits..Cast Boolits ;)

Very good ten rnd., 300 yd. group on the paper plate. Oh how I long for even a 200 yd. range.

George,
Thank you for the Mr. Borjesson\Walt DD history.

Thanks to all for the good company,
Wt.

[PAT303]

I learnt something today about cast boolits,thanks everyone who posted in this thread. Pat

[fatnhappy]

That "double d" was one of Walt's brainchilds. I always thought it sounded like a good idea, but don't really know of anybody who has tried it.

Walltube.. How did that Double D work on your 311334? I have a DC mold in that number that won't cast a nose larger than .299, no matter what alloy. Might be a good project for me to try.

Funny, my 311334 cast a .299" nose too. To make matters worse it runs .3145" on the body bands. It's quite the redheaded stepchild. Putting a double D in the nose is a roundtoit.