45-70 twist

[beng]

Have a Remington RB #1, It has a new barrel (heavy, 1-18 twist, Green Mountain 34" long) Is there a law for the size of Boolits to use? (1-18) .........100 Yards to, say, 300 yards. (not for hunting, just silhouettes, etc) Thanks beng

[Outpost75]

Trapdoor Springfield was 1:20" and stabilized 500 grain bullets to 1000 yards.

I wouldn't worry about anything your shoulder can stand in a 1:18"

[jednorris]

When I bought a Green mountain barrel they stated the dia. of the lands and grooves. I would select a bullet .001 - .002 over the grooves. If you are just getting started I suggest you go no less than a 400 gr. bullet. Someday you might want to shoot N.R.A. Black powder Silhouettes and the 500 yd. round target you need to knock over weighs #50.

[country gent]

I have 1-18 twists on 4 45 cal rifles. 1) pedersoi 34"half round, 2) BRC 1-18 twist 32" long with choked muzzle, 3) 1-18 badger 32" long, 4) 1 green mountain 1-18 twist taper octagon 34". # are 45-70s and 1 is a 45-90. All shoot their best with bullets in the 480-550 grn range. I load all Black Powder ( Olde Ensforde and a little Swiss) bullets are cast from 20-1 lead tin and lubed with SPG or Emmerts Improved. O would recommend the following 3 to try first as they seem to do well for a lot of shooters. 1) Lyman 457125 govt round nose 510 grns. this is a copy of the original bullet and seems to work well overall. 2) the lyman 535 grn postell is a very good bullet and perfoms well at longer distances. 3) Old wests moulds 547 grn silhouette bullet does well in my rifles and is an easy to cast design. The other I've had good results with is the 500 grn rcbs bullet
A good way to find what you want is to post a want add for bullets in Swapping and Selling for 25 or so bullets to test in different types. In this way you have the mould number maker lube and alloy when you find your bullet and know just what to buy. Buffalo arms sells bullets cast from 20-1 and spg lubed also to test but you may have to guess as to mould and maker.

[BrentD]

I would keep the bullets below 1.45" in length, and probably closer to 1.40". However, out to 300 yds, longer bullets may do well enough, depending on your needs (and bullet design/type).

[varsity07840]

Trapdoor Springfield was 1:20" and stabilized 500 grain bullets to 1000 yards.

I wouldn't worry about anything your shoulder can stand in a 1:18"

I thought TDs have a 1:22 twist.

[Chill Wills]

Trapdoor Springfield was 1:20" and stabilized 500 grain bullets to 1000 yards.

I wouldn't worry about anything your shoulder can stand in a 1:18"

Actually all Springfield 45-70's were 1 in 22 inch twist and even the long 535 gr Postell hits head on at 1000 yards in good to moderate conditions.

[Chill Wills]

Sorry, I just started reading this and got to the second post and replied. I should have completed reading the whole thread.

[EDG]

The answer is yes sort of. The answer is more of a rule than of a law since the proper bullets or twist for your bullets can vary some and work fine. It is a little like driving a car. Any highway speed between 45 and 70 mph is ok as long as you are getting good accuracy.

You need to be a little mathematically inclined just to read the instructions. You may need to spend an hour or two to soak up the terminology so you can make sense of the results.

There are stability and twist rate calculators on the web that are easy to use.

They will normally want the length of your bullet.
They may calculate a stability factor, a twist rate or the bullet length.
Goof around with a few of them and you will see what I mean.

http://bergerbullets.com/twist-rate-calculator/
https://en.wikipedia.org/wiki/Miller_twist_rule

I kind of like this last one.

http://www.geoffrey-kolbe.com/barrel_twist.htm

[BrentD]

the problem with every calculator I've ever seen is that they do not account for, most importantly, the distance to be shot. Stable at 100 yds is VERY different than stable at 1000. It took me years to understand this to the degree that I needed. Yes, I knew that intuitively early on but I totally underestimated the importance of this.

And then there is the wind conditions.

[EDG]

It is not really a problem other than people who only see black and white - perfect or not perfect.
Even a mediocre tool is better than no tool for purposes of learning. It does not have to be perfect.
It is more like horseshoes, hand grenades and thermonuclear weapons - getting close counts.
Otherwise you are back to empirical testing to learn.
So how many people ever shoot a serious amount at 1000 yards? Statistically just about none I suspect.
In the US probably less than a few thousand at the most. It can't be many because BPCR appears to be a shrinking sport.

the problem with every calculator I've ever seen is that they do not account for, most importantly, the distance to be shot. Stable at 100 yds is VERY different than stable at 1000. It took me years to understand this to the degree that I needed. Yes, I knew that intuitively early on but I totally underestimated the importance of this.

And then there is the wind conditions.

[BrentD]

It is not really a problem other than people who only see black and white - perfect or not perfect.
Even a mediocre tool is better than no tool for purposes of learning. It does not have to be perfect.
It is more like horseshoes, hand grenades and thermonuclear weapons - getting close counts.
Otherwise you are back to empirical testing to learn.
So how many people ever shoot a serious amount at 1000 yards? Statistically just about none I suspect.
In the US probably less than a few thousand at the most. It can't be many because BPCR appears to be a shrinking sport.

Yes, not many shoot much at 1000 yds and THAT is why it is so important to let people know the shortcomings of these calculators For many, several years of matches are nothing more than load testing because of that fact. Helping people cut to the chase and avoid these issues that stopped some of us for years - that's the whole point of these forums.

[EDG]

Unless you have a dial a twist barrel with the patented adjustable twist mechanism you are stuck with what you current barrel has. If you do not research and find the right twist to begin with it is not the fault of the twist calculator.
Useful twists for the 45-70 have been known for more than 140 years. In many of these forums you find people do their research AFTER they have bought a rifle and not before.
Not many shooters know the interactions between bullet length, twist and velocity.
Any tool that helps is good. No many people expect to see the spikes in the graphs at in the transonic ranges. Saying the models are not perfect helps no one if you do not offer an alternate solution.
In the case of a stability calculator you may only need to increase the stability factor lower limit to insure best long range performance. Load testing at a match is something of an indication of lack of research before the fact. There is plenty of written commentary by experienced shooters that identifies the need to have a stable bullet at the maximum range you shoot at.

Yes, not many shoot much at 1000 yds and THAT is why it is so important to let people know the shortcomings of these calculators For many, several years of matches are nothing more than load testing because of that fact. Helping people cut to the chase and avoid these issues that stopped some of us for years - that's the whole point of these forums.

[BrentD]

edg, you are stuck with the barrel until you rebarrel. But you are not stuck with the bullet unless you really do not want to buy or fix your mould.

As a somewhat experienced shooter and user of many different bullet stabilization/twist formulas, I sure wish I had known a whole bunch more about this topic back in the day. And that's why I post what I do here.

Knowing that models are not accurate is a HUGE help. Even better is knowing that the lack of model precision is biased in one direction. Knowing when and where the models are least reliable is great help.

People like to say that useful twists have been known for .45s for years. I will beg to differ a bit on that. 140 years ago, 20" twists were common, 18s not so much. Now the 16s are in the winners' circles with much higher frequency than they are found on the firing line. The future of long range .45s is almost certainly 16" for anyone contemplating new rifles or barrels.

What people don't know is exactly what this list is supposed to help with. So, use the calculators with caution and expect them to fail on the liberal side of things and that this problem gets worse with target distances and quartering head winds. So compensate for that by considering that you may want faster twists and/or shorter (and thus lighter) bullets (and maybe more pointed as well.

And, just for the heck of it, I will add that I think the twist calculator biases and errors are somewhat larger for paper patched bullets than grease grooves.

[EDG]

I have experience with a dozen 45-70s plus a few other calibers since 1972. I do not remember a single one that had an inadequate twist rate.
As I see it you are using a circular argument in which you shifted the barrel twist to the length of the bullet. Of course you are not stuck with the bullet if you don't mind buying additional molds because you did not get the right one to begin with. Then you have to replace it because you did not do your research up front. But anyone that reviews the topic of bullet stability will discover that the formulas were backed into from empirical testing. They are not based on pure mechanics. I think the calculators are excellent tools for those willing to think as opposed to those who tend to accept the out put of a model as a perfect result.
I pretty much disagree with your analysis of twist since almost NO one is going to be willing to rebarrel a rifle with $500 barrel just to gain 2" of twist. If you are a "spend any amount to compete sort of person" I suspect there is nothing that will make you happy.

edg, you are stuck with the barrel until you rebarrel. But you are not stuck with the bullet unless you really do not want to buy or fix your mould.

As a somewhat experienced shooter and user of many different bullet stabilization/twist formulas, I sure wish I had known a whole bunch more about this topic back in the day. And that's why I post what I do here.

Knowing that models are not accurate is a HUGE help. Even better is knowing that the lack of model precision is biased in one direction. Knowing when and where the models are least reliable is great help.

People like to say that useful twists have been known for .45s for years. I will beg to differ a bit on that. 140 years ago, 20" twists were common, 18s not so much. Now the 16s are in the winners' circles with much higher frequency than they are found on the firing line. The future of long range .45s is almost certainly 16" for anyone contemplating new rifles or barrels.

What people don't know is exactly what this list is supposed to help with. So, use the calculators with caution and expect them to fail on the liberal side of things and that this problem gets worse with target distances and quartering head winds. So compensate for that by considering that you may want faster twists and/or shorter (and thus lighter) bullets (and maybe more pointed as well.

And, just for the heck of it, I will add that I think the twist calculator biases and errors are somewhat larger for paper patched bullets than grease grooves.

[BrentD]

Okay, come knock us all dead with a 22" Trapdoor. Oak Ridge on Friday next week.

Lots of people rebarrel for 2" of twist. I'm just one of them.

[EDG]

Ok but you have to wear buckskins, leave your false teeth and eye glasses at home and show up riding a mule. After all you want to be the perfect BPCR kind of throw back right?
But which side of the argument are you on?
Is a 16.5" twist better than a 16.25" twist?

Okay, come knock us all dead with a 22" Trapdoor. Oak Ridge on Friday next week.

Lots of people rebarrel for 2" of twist. I'm just one of them.

[BrentD]

Sure thing.

We will all be looking for you.

[EDG]

Sure thing but, how to I tell the mules from the shooters?

Sure thing.

We will all be looking for you.

[BrentD]

Sure thing but, how to I tell the mules from the shooters?

You are a smart lad, I'm sure you will figure it out, but to be helpful, if it is someone that looks like you, it's not me or another shooter - it's a mule. Work it out from there...