Page 2 of 2
Re: PMC factory ammo
Posted: Sat Jul 17, 2010 4:14 am
by JamesH
jbshooter wrote:How do you explain the PMC factory ammo with it's 100gr HBWC and low velocity. I don't get any bullet tumbling with it. Do you think it's a real slow powder? It's certainly a soft load when it goes off!
Bullet size happens to fit your barrel.
Posted: Sat Jul 17, 2010 8:05 am
by buonvento
Unfortunately I have a 550B.... By the way Dillon makes a spare powder funnel for .32 wadcutter. I don't know why they don't sell a die set for centerfire shooters!
Posted: Sat Jul 17, 2010 3:12 pm
by jbshooter
When measuring (slugging) the barrel are you measuring the barrel inside diameter in the grooves or the rifling inside diameter (smaller)?
Posted: Sat Jul 17, 2010 3:39 pm
by Tony C.
When slugging a barrel, I measure the land to land dia.
If your barrel has land to land dia. of say .312", you should size your bullet to .312"-.313" or so, as well you'll need to size your brass sligtly undersize around .310"-.311" so it can have a good even grip of the bullets.
Properly sized bullets and brass has greater impact on the rounds accuracy then what kind of powder charge is being used. I think that is the reason why factory ammo are often perform better than handloads, at least in the context of handgun match ammo, because they are far more consistant in terms of the size of bullets and brass, as well as the crimping being applied.
Posted: Sat Jul 17, 2010 5:15 pm
by David M
Measure across the lands (largest diameter).
For soft cast bullets go 1 to 1 1/2 thou larger than land size.
Neck size for your bullet sized diameter. There is a natural 1 to 2 thou spring back in the brass for case neck tension, this is sufficient for target loads.
The secret for factory loads in .32 is new brass. For competition loads either load with new brass or neck anneal each time you load. This difference is not as apparent with .38 due to the thicker cases.
Posted: Sat Jul 17, 2010 7:28 pm
by jbshooter
Maesuring inside the barrel I've got 0.314"to the outside of the grooves and 0.308"to the insides of the lands if that makes sense ie grooves are cut 0.003"deep per side. I usually use Hornady 90grHBWC, 0.3145"actual diameter. I have used Lapua 100gr, also 0.3145"actual diameter. I pulled a bullet from the PMC factory round (most accurate one) and it measured 0.313"diameter. What size do you think I should resize my projectiles to?
Posted: Mon Jul 19, 2010 2:01 am
by j-team
David M wrote:Measure across the lands (largest diameter).
Errrrr. The lands are the smaller diameter, don't you mean grooves?
Posted: Mon Jul 19, 2010 4:56 am
by David M
You slug the barrel using a over size soft lead slug, driven thru the barrel.
Measure the largest diameter of the slug. ie across the lands of the slug.
It is virtually impossible to directly measure inside a barrel.