Alright I've been reloading for my 45 acp for about a year now and they work- shoot good. How ever I just bought a brand new 45 and it wont fully chamber the rounds. I'm using 230 gr. RN cast. do I just need to start making them a little shorter for my new pistol? and if I do that will my older pistol still shoot them alright? Thanks.

Well, the first thing you need to do is find out WHY the rounds are not chambering in your new .45.

Start out by field-stripping it. Then take an empty, resized case (that fits OK in your old gun), and see if it will fully enter the chamber of your new pistol. It should come just flush with the rear edge of the barrel projection that touches the face of the slide when the slide is in battery. If it is SLIGHTLY SHORT of that edge, it's still OK. If it sticks out beyond the barrel chamber, it is too long and the case needs to be trimmed. I use my .45 ACP chambers as a cartridge length gauge, and trim all cases to fit each chamber. I realize this would be a lot of work if you have more than one pistol, and you might not want to have to keep the loaded rounds separate for each one. So, they need to be custom-fit to your SHORTEST chamber. (ALL chambers SHOULD BE the same depth, but I find that they often are NOT!)

Assuming that the BRASS fits your new barrel OK, the next check is madeto try to determine what it is about a complete round that is hanging up-is seating a bullet expanding the case necks too much, so that they exceed the diameter of the chamber throat? Mikethe first.2" of an inch of the empty case, and do the same with a complete round. Are they the same diameter, or is the loaded one bigger?If so, you may need to use a smaller bullet diameter-this depends on the difference in the two measurements.

Another thing to check is, does the bullet itself contact the chamber throat or the beginning of the rifling somewhere on the surface of the bullet? If so, it will usually make a mark on the part of the bullet that contacts the chamber throat or rifling.

I think you can see where this is going-you find out WHAT about your rounds are causing the problem. Then you figure out how to deal with it.

I will try to help you further with this problem, just let me know what you discover with the new gun's barrel and your ammo.

Well thanks to eldequello I think I know whats wrong. My cast bullets are sized to a .452 witch is expanding the brass just enough so it wont chamber in the new pistol. Now if I drop down to a .451 will this be enough to fix it? Thanks.

I don't think thats the problem. What is the make and model?

I have a hard time believing that a .452" bullet is causing the problem also.

If you lock the slide back, can you manually push one of your reloads into the chamber?
If so, does the cartridge hang up about 1/3 of the way into the chamber when fed from the magazine?
-If this is the case, try seating the bullet out a few thou, with your 230 gr RN bullets I'm betting that there is a small shoulder on the bullet just in front of the lube grooves- this needs to stick out of the case a hair (I used the imprecise term 'hair' because I can't remember the exact number I use on 200gr SWCs- Its about .001-005")

Did you set your crimp die to remove the belling on the case mouth? Not crimping the mouth bell back down will make it not chamber.
You don't want to overcrimp a cast bullet because it will squeaze the bullet down making for a loose fit- just give it enough crimp to remove the belling and give a slight amount of tension. A reloaded .45ACP with a cast bullet will often look somewhat coke-bottle shaped.

The pistol is a RugerP90DC 45 Auto.

ruger357w, have you tried any factory ammo in your new pistol? If so, how does it feed? If it works OK, you need to compare the external dimensions of your handloads to those factory rounds that work OK - length. and the diameter at several ponts on the cartridge case, such as case mouth, midway back, and just in front of the extractor cut.

A .452" bullet COULD be the problem. But if so, you have a very tight chamber! Did you try just using the barrel as a "cartridge gauge" as I suggested? If so, what id you learn?

I seem to recall that GI Ball ammo used bullets that were quite a bitunder groove diameter, and that this caused excessive gas-cutting, thus considerably reducing barrel life. I just don't remember the size of those bullets, but I believe they were around .450". I also don't remember WHY the Army used the small bullets, unless it was related to a need for reliable feeding under combat conditions.

You could load up a couple of dummy rounds with .451" bullets and see how they fit into your chamber. If they go all the way in, load them into the magazine and see how they feed.