Pressure signs

DBateman

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I am after a good explanation on identifying signs of pressure particularly through measuring the case head expansion. I have always gone off of bolt opening, primers flow and extractor wipe ect but I think that really only works well on bolt guns ?

Can anyone recommend a book or a writeup somewhere ?

Thanks.
 
It has been written more than once that you can achieve 70,000 psi ( i.e. Piezo pressure) without visual evidence.

Best book for case head expansion method is 'Pet Loads' by Ken Waters.

Velocity is also useful. John Barsness wrote an excellent article:

Some Truths About Chronographs: What do they tell us?' Handloader # 204, April-May 2000. He also made brief reference to his findings in:

'Cartridge Expansion: A Modern Look at Determining Safe Pressures' in Handloader # 288, February 2014.

Yes ... You could try to cheat by simply reading Mr Barsness' latest article BUT the safer course is to read the first chapter in Pet Loads, following up with a perusal of the individual articles in that book ( well worthwhile)

AND THEN ...

Read the April 2000 article by John Barsness.

I assert that you will eliminate a great deal of confusion and save potential damage to people and firearms by doing so!
 
Thank you for your reply ZG47.

It has been written more than once that you can achieve 70,000 psi ( i.e. Piezo pressure) without visual evidence.


That is what I'm worried about, by the time I see pressure signs I'd be way over pressure
What has been working in my boltguns just doesn't seem like it would be the right approch for levers and doubles ect.


I will hunt down a copy of Pet Loads by Ken Waters.
 
Is anyone able to recommend a good place to purchase a few books.

One being the above mentioned Pet Loads by Ken Waters also shooting the british double.

I did try Amazon but they won't ship some things to Au and those books are two of them.
 
D
Go direct to the publisher, Wolfe Publishing, for Pet Loads.

Type in Wolfe Publishing, Rifle Magazine or Handloader Magazine. Any of those should get you where you need to be!

If you want to buy stuff in the West Island:) try Skennerton's website or possibly one of the bigger gun shops like Horsley Park.

Let us know how it pans out.
 
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That is what I'm worried about, by the time I see pressure signs I'd be way over pressure
What has been working in my boltguns just doesn't seem like it would be the right approch for levers and doubles ect.

The italicized part is spot on.

Levers and doubles have one thing in common...they are generally chambered for cartridges that operate at relatively low pressures (note the words "generally" and "relatively"...there are exceptions).

So you are absolutely correct in your thinking that you do not want to approach these rifles like you might a bolt action, when it come to exploring the upper limits.

Personally, I'd use established starting load data and a chronograph, and go from there...never trying to set any new speed records with either platform type. Find a load to your liking near the long-established factory velocity levels and call it good.

At the risk of beating the dead horse, we all know the bullet you use and where you put it is always way more important than 100 fps.


Tim
 
Personally, I'd use established starting load data and a chronograph, and go from there...never trying to set any new speed records with either platform type. Find a load to your liking near the long-established factory velocity levels and call it good.

At the risk of beating the dead horse, we all know the bullet you use and where you put it is always way more important than 100 fps.

Well said, I'm with you.
 
D
Go direct to the publisher, Wolfe Publishing, for Pet Loads.

Type in Wolfe Publishing, Rifle Magazine or Handloader Magazine. Any of those should get you where you need to be!

If you want to buy stuff in the West Island:) try Skennerton's website or possibly one of the bigger gun shops like Horsley Park.

Let us know how it pans out.

Thanks mate I'll give those a look.


The italicized part is spot on.

Levers and doubles have one thing in common...they are generally chambered for cartridges that operate at relatively low pressures (note the words "generally" and "relatively"...there are exceptions).

So you are absolutely correct in your thinking that you do not want to approach these rifles like you might a bolt action, when it come to exploring the upper limits.

Personally, I'd use established starting load data and a chronograph, and go from there...never trying to set any new speed records with either platform type. Find a load to your liking near the long-established factory velocity levels and call it good.

At the risk of beating the dead horse, we all know the bullet you use and where you put it is always way more important than 100 fps.


Tim

Well said, I'm with you.

Normally I do use loads that are in published manuals and research and see what others are doing.

However I am currently working on a round and powder combination that I have not been able to find published data for nor have I been able to find much forum chatter about it, hence my question regarding information on ways to accurately monitor pressure.
 
What cartridge, bullet and powder?

Someone here just might be able to give some specific guidance.
 
One of my buds is a military Small arms light weapons tech with a passion for all guns. He told me never push a cartridge to its limits get a bigger gun.
 
Check out www.loaddata.com. there seems to be a lot of reloading recipes on there. And, if you sign up, you get a nifty binder (y)
 
What cartridge, bullet and powder?

Someone here just might be able to give some specific guidance.

The cartridge is the 348Win powder is RL-19 topped with a Woodleigh 250gr bullet.
The only info I have been able to find is a few mentions of 60gr loads giving good accuracy, which it does.
And some info on www.loaddata.com but using the max loads listed on that site I am only getting 2190fps and I would like to be able to push the bullet a little fast and try and reach factory velocities or close to.

2190fps is a fair bit under the velocities listed on www.loaddata.com

I am thinking of buying quickload but I would still like to be able keep an eye on pressure signs as I work up a load. I'm also wondering if the browning that fired the rounds on loaddata has a quicker barrel than mine and how much of a difference 250gr Hornady vs 250gr Woodleigh would make in the velocity field.

One of my buds is a military Small arms light weapons tech with a passion for all guns. He told me never push a cartridge to its limits get a bigger gun.

I'm only wanting to reach factory performance.

Check out www.loaddata.com. there seems to be a lot of reloading recipes on there. And, if you sign up, you get a nifty binder (y)

I didn't get the binder. I thought the postage over to here wouldn't be worth it, is the binder any good ?
I just use a ring binder thing at the moment.
 
The cartridge is the 348Win powder is RL-19 topped with a Woodleigh 250gr bullet.
The only info I have been able to find is a few mentions of 60gr loads giving good accuracy, which it does.
And some info on www.loaddata.com but using the max loads listed on that site I am only getting 2190fps and I would like to be able to push the bullet a little fast and try and reach factory velocities or close to.

2190fps is a fair bit under the velocities listed on www.loaddata.com

I am thinking of buying quickload but I would still like to be able keep an eye on pressure signs as I work up a load. I'm also wondering if the browning that fired the rounds on loaddata has a quicker barrel than mine and how much of a difference 250gr Hornady vs 250gr Woodleigh would make in the velocity field.



I'm only wanting to reach factory performance.



I didn't get the binder. I thought the postage over to here wouldn't be worth it, is the binder any good ?
I just use a ring binder thing at the moment.

Binder is totally not worth it unless you have a need to spend $20 on a binder (which I apparently did lol)
 
I'm only wanting to reach factory performance.


Some guns never will get to "claimed factory performance" due to loose chambers etc. Further factory ammo uses powder mixes to achieve necessary performance in their "test barrels". Test barrels are for lack of a better term perfect SAAMI spec with very nice bores. I would let pressure signs be the judge of how far to push. If you use a soft primer like Win they crater and flow at much lower pressures than CIL. I use a blade micrometer and measure case heads if going for a hot load. I'm so careful that when developing loads in the winter I bring a cooler to keep the ammo at 70 deg so as not to get a nasty surprise in warmer weather.

my $.02
 
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I don't want to hot rod the round, all I am wanting to do is see what I can do with what I have.
Without hurting myself or my rifle.
 
All of the above mentioned methods are great. I purchased a copy of 'Pet Loads' by Ken Waters early on in my reloading life and have never been sorry. I have developed a lot of loads for which there were no recipes for with great results and no problems. Get a good set of digital calipers and a chronograph. Always measure before and tag the brass with an entry in the notebook. Measure immediately after extraction (warm) and then a few minutes later (cold). Put this in relation to the chronograph velocity and then you can tell where your pressure spikes are on the upper ends. Good luck and stay safe.
 
Thanks Nicholas, I have Pet Loads on the way looking forward to having a read.

I expect it to arrive tomorrow.

I have a chronograph already and a set of vernier calipers but I'm finding I have to go out in the sun to read the scale nowadays, must be getting old. I've been thinking of going to a dial caliper.
 
Thanks Nicholas, I have Pet Loads on the way looking forward to having a read.

I expect it to arrive tomorrow.

I have a chronograph already and a set of vernier calipers but I'm finding I have to go out in the sun to read the scale nowadays, must be getting old. I've been thinking of going to a dial caliper.
I have the same disease. Went digital.
 
I am after a good explanation on identifying signs of pressure particularly through measuring the case head expansion. I have always gone off of bolt opening, primers flow and extractor wipe ect but I think that really only works well on bolt guns ?

May I assume you're loading for a lever action rifle? If so, you should go by a load listed in a reloading manual unless you wish to purchase pressure measureing equipment. Trying to estimate pressure by measuring head expansion might not be safe. You CANNOT assume that you will be able to achieve listed factory velocities in your rifle nor can you assume that just because velocity is what some load manual lists that your load is safe. I see it bandied about a lot about how a chronograph is needed for reloading to see if a load is safe and the pressure not too high; that's a bunch of baloney.

A strong bolt action rifle is a different story. Give me a safe starting load and I can independently come up with an optimal load and maximum load with any powder and do it safely. Knowing how to do that goes somewhat beyond measuring case head expansion, looking for bolt wipe, etc.
 
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May I assume you're loading for a lever action rifle? If so, you should go by a load listed in a reloading manual unless you wish to purchase pressure measureing equipment. Trying to estimate pressure by measuring head expansion might not be safe. You CANNOT assume that you will be able to achieve listed factory velocities in your rifle nor can you assume that just because velocity is what some load manual lists that your load is safe. I see it bandied about a lot about how a chronograph is needed for reloading to see if a load is safe and the pressure not too high; that's a bunch of baloney.

A strong bolt action rifle is a different story. Give me a safe starting load and I can independently come up with an optimal load and maximum load with any powder and do it safely. Knowing how to do that goes somewhat beyond measuring case head expansion, looking for bolt wipe, etc.

As I have already stated I cannot find any manufacturers published data for the round and powder combination.
If I could find good data I wouldn't be looking for ways to determine whats safe and whats not.

I'm not assuming anything. If I were I'd just keep dumping powder in the case till I got the velocity I wanted.

What pressure measuring equipment do you recommend ?
 

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