high velocity with cast.

[35 shooter]

Okay found an answer to my post here about what was possible with 10 and 12 twist bbls. and velocity and what was being tried in that regard.
By accident i found Larry Gibson's tests with those twists in 308 i believe on the NOE forums. Thanks for your time and results on that with the xcb boolit...very impressive, especially the 12 twist. I think that will help a lot of folks obtain a bit more velocity with what they may have along with good load tecnique.
And yes i know a 14 or 16 twist makes it easier. This spring or early summer i plan to go that route with an 06 in 14 twist with the xcb boolit and beg goodsteel to build it for me using the xcb reamer for a good tight fit with that boolit.
Should be a fun project and just use some of the 06 brass to neck up for my 14 twist 35 whelen too.
If anyone is interested in getting a bit more from a 10 or 12 twist they have on hand "right now" in 30 cal. you may find Larry's tests on the NOE sight very helpful. At least i did.
Not trying to start an argument on twist rates, but this is a discussion on high velocity and i'm interested in just what can be done with all of them.
As has been mentioned in one post here i hope the continued interest and testing for high velocity here on this forum results in more interest from the factories in putting 14 and 16 twist bbls. on some of their rifles.

[cbrick]

I have a 140gr RCBS sillouette mold coming.
Any info on good loads for either of these would be appreciated.

It may pay to know your throat. Here is the RCBS 6.5mm 140 gr next to the SAECO 6.5MM 140 GR #264. They are very similar bullets, both bore riders, the major difference is the length of the driving bands. I had a 6.5BR with a short throat & couldn't use the SAECO without really deep seating the bullet. The RCBS would seat flush with the bottom of the neck and still chamber. Also if your going to be looking for velocity the SAECO has a scraper groove while the RCBS does not which could, might, possibly cause telescoping under higher pressure.


Left- SAECO #264 6.5mm 140 Gr. GC
Right – RCBS 6.5mm 140 Gr. GC

Hope this helps a bit,

Rick

[PAT303]

I just wish the powers that have accomplished this feat would take rattlesnake charlies list (which is a very good start for jacketed reloading accuracy. which I did for years as a 1000 yd Bench rest shooter) break it down item by item and give some details for what works for them
Its to all of our benefit if we share our knowledge .. maybe its spurs someone else to find the next jump in velocity/accuracy with cast bullets

Thats what people have been waiting for for as long as HV has been shot. Pat

[dtknowles]

Once we get enough people wanting to discuss each item, that can happen.

All anyone with an interest needs to do is started a new thread to discuss the items on the list. I would recommend doing it one item at a time or maybe two. Is there actually any item on the list that has not been discussed extensively on this forum before?

Tim

[Smoke4320]

All anyone with an interest needs to do is started a new thread to discuss the items on the list. I would recommend doing it one item at a time or maybe two. Is there actually any item on the list that has not been discussed extensively on this forum before?

Tim

It may have but where..somewhere on the forum of how many threads and posts.. Here we have the discussion on HV with cast but only clues to what it takes. It would be very helpful to the masses here if its all/most disseminated in one spot/thread..
Again Help give a leg up and you just never know who will return that favor with the next big discovery..
I would be more than happy to discuss the lengths we took in just case prep to get 50 good cases to shoot a 1000 yd match .
Most people here would probably stop just after hearing the amount of prep time that took but hey I am willing .. At least they would know

[Nrut]

Did either of the last three posters read post #494 on this thread??

Have you read this thread: ??
http://castboolits.gunloads.com/show...Yard-6-5-Swede

[DrB]

either way,, they seemed good to me.
you do run into degrees of difficulty along the way.
airc it was Felix that told me it was about every 250-300 fps.
21-24-2700 seemed to each hold an accuracy node.
as you found each one you found accuracy again about that much higher and had to work harder and harder on narrowing down the details to move to the next one.

If anyone has data that shows a kind of period for group size with velocity (rpm) that would be neat.

There is a phenomenon called "roll resonance" that occurs with spin stabilized bodies in atmosphere that I was looking at a few years ago in this context... I didn't bring it up on the forum because I hadn't done my homework to see if it was plausible in this context (I'm familiar with it in the context of reentry vehicles). You can find a technical pub or two on DTIC. Still haven't done the math and I'm not likely too... I'll leave it to others.

Anyway, my point is there is some plausibility that if the bullet isn't suffering damage in the bore, speeding up might increase your accuracy at moderate ranges (bullet will eventually slow back down through the resonance nodes at range... if resonance nodes do practically exist for cbs).

Roll resonance depends on asymmetry between inertial and aerodynamic centers of the body. A perfectly balanced body departed from the crown wouldn't be susceptible... but those don't exist.

I've not revisited my own high velocity (3200 fps) hornet experiments... but I expect they are in the archives.

Paper patched bullets could still show roll resonance (but they seem less susceptible to in bore damage that affects accuracy), and I would think quality swaged might be less susceptible than cast (I'm assuming swaging results in a better balanced bullet).

DrB

[45 2.1]

What I've gotten out of this thread by just reading it in one sitting today:

Use brass of the same manufacturer and lot.
Uniform the primer pocket and flash hole.
Keep neck tension on the bullet low.
Uniform the case neck thickness.
Use primers from one manufacturere and lot. (This will be tough for me.)
Try different slow burning powders that preferably fill the case.
Use a bullet matched to the velocity. Toughness is more important than hardness (think brittle).
A larger bullet diameter may help center the round in chamber/throat. Being centered is important.
Bullet alloy may not be as important as originally touted.
Bullet lube is not that important.
Consistency is king.

Thanks to the OP for starting this discussion.

As for the off-topic posts, they detracted from learning and enjoyment.

Numbering the above items:
1. Use brass of the same manufacturer and lot.
2. Uniform the primer pocket and flash hole.
3. Keep neck tension on the bullet low.
4. Uniform the case neck thickness.
5. Use primers from one manufacturer and lot. (This will be tough for me.)
6. Try different slow burning powders that preferably fill the case.
7. Use a bullet matched to the velocity. Toughness is more important than hardness (think brittle).
8. A larger bullet diameter may help center the round in chamber/throat. Being centered is
important.
9. Bullet alloy may not be as important as originally touted.
10. Bullet lube is not that important.
11. Consistency is king.
12. etc.........

Lets keep in mind that this is for the multitude of factory produced rifles (commercial and military) out there... NOT custom or rebarreled items of various vintages. Lets keep it simple without items that make no difference to the level of shooting we normally do.

Item #1. Use brass of the same manufacturer and lot

This is more detailed than it seems. Brass of the same lot from a manufacturer should be uniform in metal content, temper and dimensions. What isn't mentioned is the variance in fit to the rifles chamber. Most firearms have the lawyer safety inclusion ie. any commercial or military load know has to be safe in it at the detriment of a close fit. The problem here is one of a loose chamber, not in headspace, but in neck and chamber dimensions. This bug-a-boo is the cause for a whole lot of problems for us. Brass manufacturers vary up to 0.005" in case neck thicknesses which can help provided you can find brass so the fit is correct (really not so easy to do in quite a few cartridges). We will bring this up in more detail in items #4 and #8 among others.

Now, does anyone else want to add to this?

[dtknowles]

Numbering the above items:
1. Use brass of the same manufacturer and lot.
2. Uniform the primer pocket and flash hole.
3. Keep neck tension on the bullet low.
4. Uniform the case neck thickness.
5. Use primers from one manufacturer and lot. (This will be tough for me.)
6. Try different slow burning powders that preferably fill the case.
7. Use a bullet matched to the velocity. Toughness is more important than hardness (think brittle).
8. A larger bullet diameter may help center the round in chamber/throat. Being centered is
important.
9. Bullet alloy may not be as important as originally touted.
10. Bullet lube is not that important.
11. Consistency is king.
12. etc.........

Lets keep in mind that this is for the multitude of factory produced rifles (commercial and military) out there... NOT custom or rebarreled items of various vintages. Lets keep it simple without items that make no difference to the level of shooting we normally do.

Item #1. Use brass of the same manufacturer and lot

This is more detailed than it seems. Brass of the same lot from a manufacturer should be uniform in metal content, temper and dimensions. What isn't mentioned is the variance in fit to the rifles chamber. Most firearms have the lawyer safety inclusion ie. any commercial or military load know has to be safe in it at the detriment of a close fit. The problem here is one of a loose chamber, not in headspace, but in neck and chamber dimensions. This bug-a-boo is the cause for a whole lot of problems for us. Brass manufacturers vary up to 0.005" in case neck thicknesses which can help provided you can find brass so the fit is correct (really not so easy to do in quite a few cartridges). We will bring this up in more detail in items #4 and #8 among others.

Now, does anyone else want to add to this?

Use the best quality brass you can find, Lapua, Norma, or Hornady are at the top of my list. Use dies that match your chamber. Measure your fired brass and compare to sized brass, it they are not close either neck size or open up your dies to size the brass less or send your brass to someone who will make a die to match your fired brass. Don't pull your brass over a sizer button, it will make your necks crooked.

Tim

[dtknowles]

I will start #2 If you use quality brass you don't have to uniform primer pockets or flashholes but it can sometimes help to deburr the inside of the flashhole. There might not be any benefit to cleaning primer pockets either.

Tim

[45 2.1]

Please, let's take one item at a time to completion before tackling the next. This will become important later on. Charlie's original list is less than half there and it needs fleshed out some in the original items before adding on the rest.

[dtknowles]

Please, let's take one item at a time to completion before tackling the next. This will become important later on. Charlie's original list is less than half there and it needs fleshed out some in the original items before adding on the rest.

This is one of the reasons I thought these discussions belong in their own separate threads.

Tim

[45 2.1]

R5R set this thread up to talk about how to get there. Let's accommodate him on this since this topic has a lot of detractors...................................

[Doc Highwall]

The brass also has to have been only fired in one gun and with the same number of firings.

[dtknowles]

generally weight by volume is more consistant and a better guide than by case weight.

But to satisfy this question sort some into weight by volume and some by case weight and see if you have a noticable differance and some just thrown together by head stamp (it would be best that all samples had the same headstamp). Keep all seperated and record the results for three or more firings.
I have heard both sides and lean toward the volume but your mileage may vary.

Just buy Lapua or Norma brass and skip the weighing.

Tim

[leadman]

I have bought and used Lapua and Norma brass and do like how consistent it is is most respects. the Lapua brass is much heavier and stronger than the Norma brass I purchased for the same cartridge. Do have to reduce the loads slightly in the Lapua brass.
Right now it is very difficult to get most brass.
No one has mentioned Nosler brass. Anybody have any experience with it?

cbrick, my 6.5-06 is a low round count barrel and seems to have a very short throat. I tried one of the NOE 6.5, 145gr boolits sized to .265" and 2/3 of the boolit was in the case. Hope the RCBS will work out better.

[cainttype]

Lets keep in mind that this is for the multitude of factory produced rifles (commercial and military) out there... NOT custom or rebarreled items of various vintages. Lets keep it simple without items that make no difference to the level of shooting we normally do.

I disagree. The thread is "High Velocity With Cast", not included in the title (or OP) is any suggestion to limit the scope of the discussion to commercial and MilSurps.
Excluding "custom or rebarreled" firearms is a limiting factor, not an attempt to explore ALL options that are readily available. In fact, I believe R5R is using just such a firearm in some of his HV pursuits, as are many of the other contributers here.

[45 2.1]

is good to sort brass by wait?

Yes, it is....... for benchrest shooting in a rifle capable of shooting under 1/2 MOA. For most things, it will not matter.

The brass also has to have been only fired in one gun and with the same number of firings.

Again, this matters in 1/2 MOA capable rifles.

Just buy Lapua or Norma brass and skip the weighing. Tim

There are some other things that make a difference also, but IF you can get this brass, take advantage of it.

I disagree. The thread is "High Velocity With Cast", not included in the title (or OP) is any suggestion to limit the scope of the discussion to commercial and MilSurps.
Excluding "custom or rebarreled" firearms is a limiting factor, not an attempt to explore ALL options that are readily available. In fact, I believe R5R is using just such a firearm in some of his HV pursuits, as are many of the other contributers here.

There are already other threads accommodating that..... and since you posted in them, you know where they are. If you want to argue and disrupt here... please go elsewhere.

[45 2.1]

Use the best quality brass you can find, Lapua, Norma, or Hornady are at the top of my list. Use dies that match your chamber. Measure your fired brass and compare to sized brass, it they are not close either neck size or open up your dies to size the brass less or send your brass to someone who will make a die to match your fired brass. Don't pull your brass over a sizer button, it will make your necks crooked. Tim

Most brass is of good quality now, unlike 50 years ago. Use anything that fits better! Dies are a special matter...... they are made to put your brass back to somewhere in spec, but that may not be what you want. I've altered and polished out dies many times to better fit normal factory chanbers. The benefits in doing that are usually increased accuracy. The better the brass fits your rifle's chamber, the better the results you can get. Following case sizing instructions usually get you and undersize, out of line case to the centerline of the chamber/bore relationship. Die manufacturers have made separate decapping assemblies for a very long time..... some of these are available with a carbide expander button..... USE THEM..... because once you learn how much case neck tension/grab/resistance you want, they will tell you that when you pull the neck over them. That is a very easy way to segregate cases.

[Doc Highwall]

This is what I use to check the head space on fired cases and to set the reloading dies up for minimal clearance. I full length size cases for semi autos and lever actions, but I only neck size for my bolt guns.

http://www.sinclairintl.com/reloadin...prod55256.aspx

And this is what I use for where the bullet touches the lands.

http://www.sinclairintl.com/reloadin...prod34014.aspx