16 posts
Joined November 2009

Reloading 9mm Luger

Is it ok to use the same amount of powder and follow all other measurements while reloading 9mm Luger, 115 gr weight when using lead or hard cast alloy bullets? Thank you.
65 posts
Joined June 2016

RE: Reloading 9mm Luger

It is always wise to reduce the powder charge when making a component change to an established load that you have been using. Try to find load data for the components you have. For cast bullets, the Lyman manuals are very good. But many loading manuals offer loads for cast bullets.

Cast bullets are usually oversized to seal in the rifling grooves. If you change the alloy to a hard cast, it is possible to spike the pressure.

Yeah, that's the standard answer. Consider, no one knows your level of reloading experience. Just as no one knows mine. That's not to say that a more experienced reloader will not reduce a charge. Almost certainly they will, depending upon what they are using as a load recipe to begin with.

Loading too light can be just as dangerous as not reducing a charge when changing a component. Certain powders need to remain within a range depending upon what components are used. I will study various manuals and research online when working up a load.
41 posts
Joined December 2007

RE: Reloading 9mm Luger

As per Bob's answer (above) since the bullet material and the bullet weight are the same, the load will be close, but it may not be exactly the same. Only incremental load testing will tell.

"Close but not exactly" will be your answer for ALL variations in lead bullets, including Hi-Tek coated, powder paint coated, lubed, all the various shapes, and all the various lead alloys.

Get a published recipe for a 115gr lead bullet. Subtract the Starting Load from the Max Load to obtain a 'load range', which you should then divide by 5 to get an effective "increment". (E.g. 4.9gr - 3.9gr = a 'range' of 1.0gr. Divided by 5 equals an increment of 0.2gr.)

In cases like this you ALWAYS begin at the Starting Load. So your test loads will be 3.9gr, the next step (or increment) will be 3.9+0.2 or 4.1gr. then 4.3, 4.5, 4.7gr etc. Not to exceed 4.9gr.

You need to realize that 3.9gr (in this example) may land you in the middle of the actual Load Range. But, it could just as easily place you well below the actual Load Range. No one knows. Only the testing will tell, and a chonograph will really help you. If you load and test 5-10 cartridges at each Incremental Load, stop between each test group as you work your way to higher loads. Closely observe the spent cases for pressure signs, and compare their velocity with published numbers.

At no point should your velocity be greater than the velocity of the Max Load from the recipe. This because Velocity closely follows Chamber Pressure within the recipe load range. Realize that EVERYTHING we do in reloading is to control Chamber Pressure. We would "like" to find a load our pistol likes, we would "like" an accurate load, we would "like" many things... but we MUST always be in control of Chamber Pressure.

Hope this helps.