Thanks Joe. I knew there had to be a ratio of some kind.
Take Care
Bob
Its been months since I bought the book, "How to scam people online". It still has not arrived yet!
"If the human population held hands around the equator, a significant portion of them would drown"
Bob,
As others have brought up... I as well am confused by your statement underlined in you quote above.... Millimeters per Meter might be a possible measurement I suppose if millimeters referred to advancement of an exact point (like a particular land location) around the circumference of the actual groove diameter of the barrel over a given length. But confusing and overly complex for me!
One turn or complete 360 degree revolution of the helix seems much more appropriate to me and works fine either in metric or inches. A gain twist could be an exception.
Looking at Joe's conversions maybe the Swede was engineered with a 1 in 20cm twist possibly? The point .066 is only about .030" or about 1/32" off from 7.9".
Eutectic
Its been months since I bought the book, "How to scam people online". It still has not arrived yet!
"If the human population held hands around the equator, a significant portion of them would drown"
If you look up the 6.5 Swede twist on the internet you get anything from 7.5 all the way up to 8.9. That's crazy. Interesting is that Lothar Walther sells barrels in two categories. One is American and the other European. The differences are the bores, grooves, and twist. With that said they list the European twist for the Swed at 8.9.
Yes above I gave the twist in mm's and cm's in one turn and also gave it instead of one turn, I gave it in one meter.
Joe
Yes I googled it and got nowhere. YOu would think the twist rate would be on an European site but I couoldn't find it.
Take Care
Bob
Its been months since I bought the book, "How to scam people online". It still has not arrived yet!
"If the human population held hands around the equator, a significant portion of them would drown"
Ask the Dutchman here, I'm sure he knows.
Larry Gibson
Larry,
Talked to my Lothar Walther friend. As you know on their website they have American barrels and European barrels. He told me the bores and twist for the European are official specifications to the original manufacturer. With that said the twist for the 6.5 Swede for their barrels is 8.9.
I told him I will have to get the cleaning rod and tight jag and see what mine reads. I'm not believing that.
Joe
I know both of my M96s come out to between 1:7.8-9", I just can't seem to get it much closer than that with a tight patch.
Gear
Use of filler in the 6.5x55 cartridge for high velocity with lead boolits equaling or exceeding jacketed accuracy
- The correct (easiest to use, not the only one suitable to use) filler is the Ballistic Products: BP Original design buffer. Be sure it has not been changed from its original properties, i.e. it will NOT flow thru a funnel without help and clumps together when piled up.
- This filler is not a Do-All in that it has a specific purpose in this and other smaller capacity cartridges. Its purposes are to reduce the cartridge capacity in which it does these things: helps the slow burning powder to achieve it initial ignition pressure by bridging in the case neck/shoulder area thereby increasing initial pressure so that the powder burns very uniformly and evenly; keeps any powder gas off the boolit base along with stopping any gas cutting; compacts into a plastic solid mass which acts as a shock absorber and provides even pressure around the boolit base. After the boolit starts moving the filler plug moves into the neck out of the case thereby increasing case capacity again lowering the pressure buildup. This keeps the pressure lower than any other method I’ve found.
- To load the Swede correctly, you need to do the previously talked about things such as: reforming military thick necked 30-06 brass along with turning the case neck to 0.001” loaded case chamber clearance, a throat sized cast boolit that fits your rifle, a centered fired formed case, etc. These have been covered in detail before and can be found in the archives.
- To actually load the cartridge involves simple hand loading methods. You need dies which will accept the somewhat (0.268”+) boolit. Several die sets will not until altered. You also need a neck expander about 0.001" below your boolit diameter to expand and flare the neck with. It also helps with some powders to taper crimp the case neck lightly.
- Powder selection is fairly simple; you pick a slow for the cartridge powder. That is one which is probably one speed (or more) slower than what is shown in the jacketed data shown for the boolit weight you have. IMR 4350 and AA3100 both work here.
- How much powder do you use? Fill the fire formed sized case up to within a dimes thickness of where the body meets the shoulder of the case. Measure that amount and check it against the loading data you have looked at. It should be on the low side of published data, at least for the powders shown. This is where you adjust the load varying the powder charge from that point up to the base of the shoulder.
- How much filler do you use? Conventional wisdom says to fill it to the top of the case neck. If you do this you will NOT get a decent group. This filler DOES NOT like being compressed much. What you do is fill the case to the point where it will compress the thickness of a gas check (that will be just slightly into the base of the neck). You will want to tap the case head a couple of times at this point to make sure it is filled to that point. Seat the boolit and taper crimp slightly.
- This is not dangerous if you have some wits about you, BUT I will not assume any responsibility for what you do either. This cartridge is graduate/PHD level on how to make it work and get it to shoot at jacketed accuracy and velocity, which it will do easily if you know what you’re doing.
- You will have to make adjustments in those powder/filler levels to achieve this. There is a learning curve here. The best way is to post your group pictures along with what you did. The group size and shape will tell what needs to be done.
- You got any questions, then ask because Joe went thru this for awhile before he caught on to how it is properly done.
- Larger calibers are a problem with this method. You ask what is the problem? Just exactly what is a slow powder for the 30-06 or one of the magnum calibers? They eat most any of the conventional powders that are slow just fine. What you’re wanting for the bigger cases is really slow powder (think 20mm surplus powder here). That in itself will be hard in the fact of lighting off a hard to ignite (in smaller quantities) powder. The window to make that happen is quite narrow.
Last edited by 45 2.1; 01-06-2010 at 12:46 PM.
45 2.1
Knowledge without understanding is a dangerous thing. For a little knowledge entices us to walk its path, a bit more provides the foundation on which we take our stand, and a sufficient amount can erect a wall of knowledge around us, trapping us in our own ignorance.
Never sleep, never die
Knowledge is easy to get, but worthless if you never use it. However the info is free, so the only person you have to blame is yourself if you chose not to use the information.
Joe just about had a heart attack seeing 45 2.1 posting that. With that said here's the filler at Midway:
http://www.midwayusa.com/viewProduct...tNumber=695248
Joe
Thanks guys.
I think it is imperative that all who follow this path are responsible for their own actions. This is not conventional loading and caution should be headed.
Now for a quick question to Bob and Joe. What is the probability of having a change occur in the filler material from what is sugggested to what is suppied by the manufacturer?
Joe,
So there is not a real issue of the manufacturer of the listed product being changed by the manufacturer in mid stride while this is being worked on?
This is the actual Midway source for the buffer.
http://www.ballisticproducts.com/pro...?number=BUFFER
A call to Ballistic products verified that it has been around for over 30 years and still made from the same materials. Only minor variance is expected from their various suppliers.
That I can't answer, but I don't see a reason for them to do so. I reckon we all should buy a bunch of the stuff they have now. I can't speak for 45 2.1 but being he has done this a lot of years ago maybe the Midway brand isn't the brand he used. It is the right type though.
Joe
I routinely purchase shotgun components from BP and as such will go that route when time is right.
45 2.1 Thank you for posting the info. Can't wait to see how Larry Gibson does with it.
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |