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Things that are making me go Hmmm.



Please excuse my reloading ignorance. My Dillon 550B will be here Monday along with the Speer 13 & Lyman manual.
I know I will have a lot of reading/researching to do. I also have a friend that has several years of reloading experience that will be mentoring me as well.



I hope somebody can help me with this subject. I plan to shoot production class in USPSA/IPSIC events with my MP 40. I have questions about working a load down to a certain power factor to meet close to the minimum PF of 125. Power factor is defined by bullet weight X velocity/1000.



Using this load as an example:

Bullet 180 Gr. JHP

Powder WSF 5.0 Grs

Velocity 860 Pressure 22,900 PSI



Assumed PF 154.8





My questions:

If I used 10% less powder will the velocity drop by 10%? If that is true, then the *new assumed* PF would be 180 X 774/ 1000 = 139.3 which is about where I would like to be.

Is there a linear relationship between plus or minus powder and plus or minus velocity?

What happens to the pressure if powder is reduced?

What are the working max & mins of pressure for .40SW?

What happens to accuracy as the load decreases?

Am I on the right track?



Do any of you use a hardened lead wad cutter bullet for practice? My thoughts would be no. I could see using lead in a revolver just not in an auto pistol like the MP Methinks the lead would coat the barrel too much.



What do most of you load for target practice/range use?



What are some of the *cleaner* powders that you use?



Thanks in advance for any & all comments.



Best regards,

Throwin Lead
 

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You can never count on velocity decreasing proportionally to powder charge, it would be nice if it were that simple, but nothing is that easy!



Pressure normally goes down with the powder charge.



Accuracy often gets better on lower charges, but again, you can't take anything for granted, you have to experiment to find the best load in your pistol, every pistol will be a little different.



I haven't used lead bullets in my 40 but I shoot them a lot in 45 acp, lead bullets will almost always leave lead behind in the barrel, and it would need to be cleaned out, I think a lot of the guys shooting competition are shooting plated bullets these days. If you want a clean load you definitely don't want to shoot lead bullets, they are lubricated and the lube vaporizes when you shoot them, it gets all over everything, lead bullet shooting is very dirty.



I'm shooting 5.6 gr of Unique behind a 165 gr Berry's plated flat point, I'm averaging 944 fps with that load out of my MP40, it's a fairly clean shooting load. A lot of guys use WW231 and it's a good powder, just keep in mind that WW231 is a fast powder, you use very little of it, it's such a small amount that you can double charge a case and not be able to tell by looking at it. For a new reloader, or one just going into a progressive press, a slower powder would be safer, that's one thing about the Unique load I use, a double charge of it will fill the case to the rim, pretty obvious it's overcharged.
 

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Precision bullets (www.precisonbullets.com) has very fine lead bullets. They coat them with something that helps w/ leading. I have used their 185 gr. bullets since last summer and love them. I also use their 200 gr SWC in my 45's with good results. I've been reloading for thirty years. You will love your new Dillon...congrats on a great decision. My advice is to read and read very carefully. Have fun working up your favorite loads. Regards
 

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I will second the precision coated bullets, they work exceptionally well and don't lead the barrel much at all. They also don't use wax so one less source of junk. I also notice a good increase in velocity using them over the plated, same weight bullet, same weight charge, my power factor went up by almost 10.



I use the 200 grain bullets with a pinch of AA#5. The load leaves a lot of unburnt powder but is really is as close to cheating as you can get without cheating.
 

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Precision bullets are coated with some kind of special coating, I've read that it's supposed to be pretty good, and doesn't have a lot of the disadvantages I mentioned for regular lead bullets.



I don't have any personal experience with them, I've just heard about them.



http://www.precisionbullets.com/
 

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My .40 minor load power factors out to 140.

Bullet either Precision Delta 180 JFP or Zero 180 JHP at an overall length of 1.135"

3.5 gr Tight Group powder

Fed or Win primers



This load is accurate and soft shooting minor load we shoot in XD, Glock, Para, Brazos, and should work well with M&P too. I don't have and M&P in .40 yet, all I have is the 9. Waiting on a tactical 5" 40 to come out.]
 
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