Fine tuning loads lee factory crimp die

[Petey308]

I don t have any mandrel dies. I measure wall thickness double then add dia of bullet subtract the desired amount of neck tension to come up with bushing size. I have K and M mandrels . I would have to determine if it adds run out, and have no way to judge if it increase the rate work harding occurs. could be a interesting side test.

I use K&M mandrels too. Their mandrels in their press adapters is what I'm referring to as a "mandrel die". That being said, I also have some mandrels that were made for me by a friend that work in a Lee bullet seating die in place of the seating stem. It's similar to a Sinclair mandrel setup. It works very well too.

 

[JDD]

Brass is made by a series of draws. As in the brass starts out as a cup and is gradually drawn out to its cylindrical shape. That process makes thicknesses uneven. It's just the nature of the beast. Because if this, if you use a bushing die without turning the necks, you're pushing those inconsistent thicknesses to the inside diameter of the neck. That results in an inconsistent amount of tension on the bullet which equals inconsistent pressure and velocity.

A mandrel pushes those inconsistencies to the outside diameter and leaves a uniform amount of tension on the bullet. No neck turning really required.

An expander ball/button is inferior to a mandrel because it pulls and stretches the neck and shoulder back out as it exits the case. Mandrels size in a downward motion and do not stretch the neck or shoulder as they exit the case.

As we all know, the neck of the case opens up when firing. You want the neck to release the bullet evenly and consistently from one round to the next. That's why it matters having the inside wall of the neck uniform.

Once the round fires, the pressure pushes the case into the chamber walls, and pushing any inconsistencies in thickness back to the inside of the case. At that point it really doesn't matter though because you'll have to resize everything again anyways.

If you turned the necks, you don't need to do it again. If you didn't, like I said, the chamber will have pushed those uneven thicknesses back to the inside of the neck. That technically doesn't matter though, because FL sizing without an expander ball will do the same thing. The mandrel is what fixes that.

It is good practice to anneal though. A mandrel can't defeat spring-back of the metal as it work hardens. Once work hardened, those inconsistent thicknesses will spring back and tension will once again be uneven. Annealing will undo the work hardening and allow the mandrel to set uniform tension once again.

If you turn your necks, a bushing can do the same thing a mandrel does. Turning your necks is what ensures the necks are even thickness and makes it so there's not more pressure on the bullet from thicker areas of brass.

I never use a expander ball on precision ammo. If I have a dented mouth I use a mandrel from my turning gear. I am going to use the km turning tools with the cutter head/ reamer to remove donuts. It should work out well. It will take another firing until the full benefits of turning come on board.

 

[Petey308]

I never use a expander ball on precision ammo. If I have a dented mouth I use a mandrel from my turning gear. I am going to use the km turning tools with the cutter head/ reamer to remove donuts. It should work out well. It will take another firing until the full benefits of turning come on board.

Sounds good. I use K&M's neck turner as well. I use the cutting pilot as well to ensure I don't have any donuts or uneven thicknesses on the inside diameter of the necks.

 

[gator378]

this is a long range site and as far as i know "crimping" does not fit anywhere in that picture. Crimping is advertised as improving accuracy and as such is a credible subject for long range hunting shooting etc. I would like to know myself
if pistols or ar's maybe ask there.

 

[ar10ar15man]

wrong
every firing will change the characteristics of the brass.
just because the standards for hunting are low does not mean a test can be done to hunting standards and be valid,

Some brass, like Lapua, Peterson, Alpha, etc are made to high quality standards and can be trusted to not require annealing out of the package. You can also get away with not annealing them after several firings. If you want absolute consistency though, annealing after every firing is best. That way it resets any work hardening.

Other brands of brass would highly benefit from a good annealing right away.

 

[Petey308]

Rephrased question to be more specific. I am not interested in hear say o on knowledge gained from first hand testing. The second aspect of questions is about tuning loads. My extreme spreads are touching on 20 I would like to cut that in half Most of my shooting is at1000 to 1200 yards

Here are the absolute best ways I've found to lower ES:

*Increase your neck tension. A good amount I've found is .003" And yes, a FCD can do this for you, but I've already gone on at length about how it's inferior to just making the the whole neck uniform.

*Use a powder scale capable of measuring to an accuracy greater than .1gr

*Use a comparator to measure your OAL from the base of the case to the ogive of the bullet. That will ensure the most consistent seating depth from round to round.

*Use match grade primers

*Batch sort your brass by weight. Absolutely don't mix headstamps or lot numbers.

Other things can help, but are ways to split hairs, ultimately. If your ES is 20fps or above, you're missing one of the above steps. Fixing it with a crimp isn't the way to go about it, in my opinion and experience. When you get your ES to 10fps and desire lower, then you can add more tedious steps lol.

Sorry, I like this thread and can't let it die lol.

 

[ar10ar15man]

it you do not control the variables in a test, the test is not valid. too many variables to make a claim.

 

[JDD]

wrong
every firing will change the characteristics of the brass.
just because the standards for hunting are low does not mean a test can be done to hunting standards and be valid,

yes and no.

I have a wild cat I shot metallic silhouette with. a 308 BR necked down to 7mm tight neck blown out and slightly improved with a 35degree shoulder . I have some cases fired 20 times and they still shot down to . 125. I made cases from 308 Lapula once formed they never saw a sizing die. I would fire deprime and seat a new bullet. It was a royal pain forming cases.

 

[Petey308]

wrong
every firing will change the characteristics of the brass.
just because the standards for hunting are low does not mean a test can be done to hunting standards and be valid,

Who said the standards for hunting are low? I sure didn't. I'm trying to be realistic. If it were me, I'd anneal all the time. I still will argue that the brands I mentioned do not require annealing fresh out of the package. I've been to a factory that manufactures brass and I've seen the entire process first hand. I'm confident that certain brands are made to standards that do not require to be annealed again right after they were annealed at the factory using annealing methods far superior to what I have lol.

There are guys that claim they've gotten 7+ reloads with Lapua brass without annealing and haven't seen a single change that could possibly be tied to work hardening issues. I can believe that, however I'd still have better peace of mind annealing after every firing.

 

[JDD]

Here are the absolute best ways I've found to lower ES:

*Increase your neck tension. A good amount I've found is .003" And yes, a FCD can do this for you, but I've already gone on at length about how it's inferior to just making the the whole neck uniform.

*Use a powder scale capable of measuring to an accuracy greater than .1gr

*Use a comparator to measure your OAL from the base of the case to the ogive of the bullet. That will ensure the most consistent seating depth from round to round.

*Use match grade primers

*Batch sort your brass by weight. Absolutely don't mix headstamps or lot numbers.

Other things can help, but are ways to split hairs, ultimately. If your ES is 20fps or above, you're missing one of the above steps. Fixing it with a crimp isn't the way to go about it, in my opinion and experience. When you get your ES to 10fps and desire lower, then you can add more tedious steps lol.

Sorry, I like this thread and can't let it die lol.

LOL I done all of the above at various times, Federal match performed worse than cci standard , they are 15 years old though could be bad.

 

[Petey308]

it you do not control the variables in a test, the test is not valid. too many variables to make a claim.

It's not that hard to change one thing, but not another. If you can't tell a difference, I'd say it's not necessary. That's the point of the test.

 

[Petey308]

LOL I done all of the above at various times, Federal match performed worse than cci standard , they are 15 years old though could be bad.

They could be. I wouldn't trust them to be consistent enough for long range work. I have 20+ year old primers though that I still use for loads that aren't detrimental to accuracy. They still go boom every time.

Methods and compounds have changed over the recent years. Those 15 year old primers likely don't have the exact same compound in them. I also won't claim FGMM primers are the absolute best. I've gotten extremely low ESs from Sellier and Bellot standard primers. I just have always had great luck with FGMM primers, so I just use them now in everything and don't worry about it.

 

[WildRose]

Its what I was thinking , are you annealing on a schuelde

If that's for me I've never been very religious about annealing. I got pretty obsessive about it back in the 90's and really didn't see a whole lot of benefit and I was loading very hot 7mm RM and .220 Swift at the time.

Right or wrong I'm convinced that the more consistent you are with neck tension the better results you will get and among all of the little fine tweaking things we come up with this has proven for me to be the most valuable.

 

[Petey308]

LOL I done all of the above at various times, Federal match performed worse than cci standard , they are 15 years old though could be bad.

If you've done all the above, and you're still getting high ES, something either wasn't done right, or you have an inferior component or piece of equipment. Is 20fps ES the best you can get out of any load during load development?