Here's an obvious newbie question, but I want to make sure I am being safe...

Are same grain/type bullets interchangeable with the same powder charge? For instance, say a manual lists 17 grains of <x> powder for a 50 grain V-Max bullet. Could you then substitute 50 grain BlitzKings or 50 grain Ballistic Tips over the same powder charge without changing pressures dangerously due to slight (if any) shape differences? I know that this would not be an option if you were changing bullet weight.

If your load is pretty close to max, changing any component requires dropping back and working back up with your load. Even changing bullets in the same weight can cause problems as some bullets engrave harder than others, or have an ogive shape that may cause it to be jammed into the lands when firing, causing higher pressures.
Taking shortcuts when handloading isn't usually a good idea.- Sheister

The lawyer answer �Anytime you change a component you are taking a chance.�

Realist answer: I will use a spear, and hornady and Lyman books to reload Sierra, remington, winchester, spear, hornady bullets (but my starting load is 10% less than their max). I will swap bullets if both bullets are of the same type and construction (FMJ-FB or JHP-BT, or JSP-FB) and the load I am using is not pushing the edge. Where people get in trouble is when they push the edge and then change a component (primer, bullet, brass). OR they swap the bullet construction type (FMJ for lead hard cast, or JHP-BT for JHP-FT).

In a general sense, no you cannot just swap the bullet type (same weight) and be completely safe. Most reloading manuals suggest decreasing charge by 5% when changing components(primers, cases, bullets) of like type. With bullets things such as sitting depth, bullet coating and bullet shape (roundnose, boattail, flatbase etc) all have an effect on pressure. This is especially important of you are operating at max pressures already with your current load.

Now from a practical standpoint, if you are shooting "light target" loads, operating well below max pressures, then bullet swapping may be safe. Would I guarantee it, NO!

As a new reloader, I would recommend you follow safe reloading procedures and not try shortcuts, it only take a few minutes to scale up your loads, after reducing by an initial 5% to determine if your switch will operate at safe pressures. I learned a lot from a man with only three fingers on one hand and one eye, he learned the hard way.

I find many hours of pleasure in reloading and hope that you enjoy the hobby as much. You will find many on this forum that are more then willing to help if you have questions.

BigBullet

Thanks for the replies...I wasn't asking because I am looking for shortcuts, rather because manuals don't necessarily list all appropriate powders for any given caliber. A bullet manufacturer will obviously only list their own bullets, so that limits you quite a bit. It would be nice to be sure that you could work up another load based loosely on the data in the manual using the same type and weight, but different manufacturer bullet...

The shape of different bullets affect how much case volume is lost when the bullet is seated. Less volume means higher pressure, all else being equal.



The bullet engraving problem Sheister mentioned is a big, big, biggie. There is an article in the old NRA handloading book. They tested conventional bullets only, no solid copper jobs such as the X bullets. All bullets were flat based and all were seated to the same depth (same net case volume) over the same charge of powder.



In this test, pressures varied from 44,500 to 51,900 CUP, and the true pressure swing (piezo psi) would have been greater yet.



Again, this was just with conventional cup-and-core bullets. The X bullets engrave harder yet.



Also seen in that test, the fps varied only 3% despite the 17% swing in pressure. A chronograph can give you a rough estimate of pressure, but it is a crude tool for this.



Still, I'd venture to say, that if you can find a reputable published load for a Barnes X of the same weight, you can match that fps (using a chronograph) with the same powder using other bullets. Other than that, backing off your fps goal 5% and loading for that with your chronograph seems reasonable.