.402 frustration fix

[thomashoward]

Hello,
Longtime reloader,but mostly a lurker here with a couple questions
I am reloading lead (Penn) WFNBB.sized .402  10mm . because my Lonewolf barrel slugs .401

My problem is these bullets cause a wrinkle that won't pass the Wilson case gauge specs.
By the time I get the bullet tension to .422 its almost a roll crimp but they chamber and eject OK.

I have used the Penn .402 with Blue Dot, seated 1.255" with a .422" neck tension before but cannot find my targets
so I begin again. Should I forget about .402 cast bullets? and just use .401?

My other load is DT 200 grain WFNGC they pass the Wilson gauge OK and shoot well. They are .401
Thanks for your input

[Henri311]

Couldn't you run them thru a sizing die to make them .401?

[The_Shadow]

Thomas, with the 0.402 cast bullets you may need to back off on the crimping die just a little, say 0.4230" or 0.4235" to alleviate your issues.  When the bullet is seated and crimp is being applied the casing can grab the bullet, (not good) this can be the source of the wrinkle as you continue to seat the bullet further into the casing if this occurs!

i KNOW IT SEEMS LIKE EXTRA WORK BUT!  You will want to do the seating and crimping in separate steps for best results. With the seating die raised, (1/8") to not allow any crimping to occur, fully seat bullets to the proper COAL.  Then run them thru the taper crimp die, without contact with the bullet seater plug (backed out),  to just apply your crimp to push the casing walls back against the bullet.

Measure just below the case mouth, and try to put the taper at the very edge of the case mouth about 0.0010" smaller/tighter.   You may even achieve the 0.4220" or 0.4225" depending on that bullet.  That will help with feeding.

Good luck!

[thomashoward]

I guess I forgot to mention I'm crimping with a Lee taper crimp die as a separate step
Just enough to take out the flair. thanks.
With the semi-auto head spacing on the mouth I don't want to alter it.
they chamber OK

[The_Shadow]

When you mentioned wrinkle I was taking that the case actually was wrinkling which can happen trying to seat and crimp in the same step.

Over crimping can cause issues of loose case to bullet fit due to spring back of the casing.  Those larger diameter bullets may be a tad to big for the case gauge, if they are fitting your chambers without issue, then you should be good to go!

I size my stuff to 0.4015" and they will fit the Lyman case gauge freely as finished cartridges and no leading with the S&W guns or the factory glock or the Storm Lake barrels for 10mm or 40S&W.

[Yondering]

Sounds like you're just overthinking it, and outsmarting yourself. If they chamber and shoot well, what's the problem? Don't worry about the case gauge, make the ammo fit your chamber and barrel.

If your barrel slugs .401", your cast bullets need to be .402"+.

I don't understand what you mean by "By the time I get the bullet tension to .422".

[Yondering]

Yep, those case gages are handy if you're loading the same ammo for a bunch of guns, but not necessary (or desirable) when loading for just one particular gun. Make it fit the gun, not the gage.

Keep your cast bullets at least .001" or more larger than the maximum diameter of your bore. If your chamber works with .403"-.404", you'd probably get even better results. Lone Wolf tends to spec overly tight chambers though.

Don't worry too much about case neck diameter. (You're not measuring tension, you're measuring diameter.) If your bullets are sufficiently hard, and sized correctly, it's not an issue.

[nickE10mm]

Sounds like you're just overthinking it, and outsmarting yourself. If they chamber and shoot well, what's the problem? Don't worry about the case gauge, make the ammo fit your chamber and barrel.

If your barrel slugs .401", your cast bullets need to be .402"+.

I don't understand what you mean by "By the time I get the bullet tension to .422".

Yondering took the words directly from my mouth.

Bottom line. If they feed and chamber, what's the trouble?

And yes, use .402 if you slug at .401. Fit is key.

[Yondering]

You need to either polish/lap the chamber out to work with cast bullets .001" larger than the bore, or stick to jacketed bullets.

Earlier you said the .402" loads chambered fine. I still don't see the problem?

[thomashoward]

They chamber now because they are seated deeper than spec, and crimped tighter than spec, but they will chamber and eject now. I'm just curious regarding the change in burning rate/pressure.

http://www.lonewolfdist.com/Content.aspx?PAGE=FAQ%20page#Reloading%20Issues:

[Yondering]

They chamber now because they are seated deeper than spec,

What spec are you trying to use with these cast bullets? You cannot use jacketed bullet OAL specs for cast bullets; cast bullet OAL dimensions will vary a lot, depending on the location of the front driving band, and how it and/or the bullet ogive fit the chamber and throat.

Pay attention to the amount of bullet inside the case, and the resulting amount of case capacity. Some cast bullet designs are bad about using a lot of case capacity; and require reduced powder charges. If the bullets you bought are that way, there's nothing you can do about it, just seat them so they fit, and reduce the powder charge accordingly.

[thomashoward]

I usually draw data from several sources. This time I looked at Hogdon, Lyman 49th ed. and Oregon Trail. Some from publications and some from Handloads.com subscription.
there are seating depths from 1.260 to 1.253 listed, I'm at 1.250
for  lyman cast bullet #401043 w/blue dot starts at 9.0 gr. going to 10.4 gr. I'm starting low as usual
Shows bullet ridge

[The_Shadow]

There are 10mm COAL that are even shorter than the 1.250", especially the WFN bullets with the larger Meplats they have been seated deeper to allow a better tipping angle of the cartridge as they feed.  Double Tap seats their WFN and some other bullets at 1.2420".

I use 10.0 grains of Blue Dot with my 200 grain cast Speer TC SWCs, seated at 1.255" they do 1200 fps from the S&W1006.

[Yondering]

I usually draw data from several sources. This time I looked at Hogdon, Lyman 49th ed. and Oregon Trail. Some from publications and some from Handloads.com subscription.
there are seating depths from 1.260 to 1.253 listed, I'm at 1.250
for  lyman cast bullet #401043 w/blue dot starts at 9.0 gr. going to 10.4 gr. I'm starting low as usual

Do not try to use seating depth specs for a different bullet! Beyond resulting in a load that doesn't fit the chamber, that can be very dangerous. The only seating depth spec you should use is one for that exact bullet. If none are published, you seat it to fit your chamber, typically keeping the OAL as long as possible with cast bullets. (by "as long as possible", I mean max OAL that fits, minus a little (.010-.040") for reliability.

The brass bulge around the bullet base doesn't look bad. It does look like way too much crimp, although that may just be the photo. I'd recommend just enough crimp to get rid of the case flare, and no more; a heavy crimp isn't needed if there is adequate neck tension.

If those still don't fit your chamber, that's a dimensional issue that Lone Wolf should fix. It is a common problem with their barrels. Honestly, you'd probably be better off with the factory Glock barrel, just make sure the bullets are larger than the bore. Even .002-.003" larger is great, as long as they don't bind in the chamber.

[The_Shadow]

In the picture posted it appears to be too much crimp to me as well.
With my RCBS taper crimp die I press the case back straight plus a pressing just a little shine on the very edge of the casing.  This translates into 0.0005" to 0.0010" depending on the length of the casings.

After the pass through the brass is ).4215' to 0.4220" and the case mouths measure 0.4210" to 0.4215" some of the shorter brass come out at 0.4220".

The important thing is not to have any bullet movement as the crimp is being applied...