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DJMajors
07-17-2011, 3:10 AM
I've recently started reloading bought a few books and thus far have followed those measurements to a t as i'm in fear of my life here. But in searching the internet for deals have noticed some brands don't have books. I was looking at x-treme bullets in 223 55 fmj and was wondering if all 55 fmj's are standard as far as grains an overall length or is there a resouce to match all bullets. Secondly what does it mean to have a plated bullet and what effect if any will this type of bullet have on a barrel.
Thanks for any help

XDRoX
07-17-2011, 7:58 AM
I would treat any 55gr FMJ the same. The heights may be a little different but not enough to create any unsafe pressures especially if you're not loading at the top end.

You'll find that there are just too many brands out there for the manuals to keep up with. I rarely find the exact data that I need in a manual. The more you reload, the better youl'll get at extrapolating data from different sources and making educated guesses.

Plated bullets have a thin copper plating. They're my favorite bullet to shoot in pistol. They're much softer than jacketed and much cleaner than lead. However data is very difficult to find for plated, so if you feel more comfortable loading rounds that you have exact data for, there's nothing wrong with sticking with jacketed until you become more experienced.

Hope this helps.

Jonathan Doe
07-17-2011, 8:04 AM
I primarily use Sierra manual and have never had a problem.

CSACANNONEER
07-17-2011, 8:47 AM
If you are talking about COAL for 55 grain bullets which will be shot from a semi auto, anything will work as long as it fits in the magazine. Also, even with different COALs on different bullet profiles, you might still have the same "jump" from where the bullet is in the catridge to where it engages the lands. Sorry, if I confused you. I can picture what I want to say better than describing it. Anyway, for basic 55 grain .223 bullets, you should be fine even as long as they fit in a magazine. If you are trying to load for maximum precision from a bolt gun, I'd suggest getting a little hands on help to help you determine the exact COAL for your rifle with each different bullet profile you intend on using.

r3dn3ck
07-17-2011, 9:02 AM
same weight same bullet material should be close enough.

If you get into "green" bullets like Barnes Varmint Grenade or DPX or anything solid copper, then you need to reduce powder charges as they have longer bearing surfaces (area in contact with rifling) and create higher pressures due to that.

In general, if you don't start near max you should be ok. The usual rules of start low and move up are easy to deal with. Even when you get off the map.

Right now I'm dealing with the fact that there's almost no data available for 6x45mm. Since I use a .223 case with a bigger bullet (6mm) I will often just use .223 data for a bullet that's 10grains lighter and start on the low end of that and work up. I know that with the powders that I use that I can completely fill the case and not go over pressure with the bullets I use so I don't often worry.

What powder do you use for .223? With IMR4895 and Varget I can basically fill the case with 55gr loads as the max charges on the jug are compressed loads that there's not enough room in the case for as it sits.

the early signs of overpressure are usually low-severity (flat primers, pierced primers, tough extraction), the late signs of overpressure are exciting and should be avoided but don't be scared, just aware. Keep low, build higher and stop before you get to overpressure.

gunboat
07-17-2011, 10:10 AM
First off, lose the "fear of your life" mentality. It is prudent to be cautious but being fearful will take all the joy out of reloading and shooting.
All the others above have given you good technical advice.

DJMajors
07-17-2011, 1:41 PM
thanks for the input I appreciatte it
DJ

rsrocket1
07-18-2011, 12:19 PM
The extreme 55g bullets shoot like standard fmjbt's. 25g H335 gets 3000 fps out of a 20" barrel and almost matches exactly PMC Bronze and Federal Value pack ammo. Seat it to the cannelure in a properly trimmed case (I go to the back edge, but anywhere in that range is fine) and no crimp is needed. The neck tension is all you need to hold the bullet in. Great rounds for plinking and can get 1" groups @ 100 yards if you bother to sort out cases. When working up loads for accuracy, you should probably start at about 23g and work up until you find good groups.

Fjold
07-18-2011, 6:53 PM
A lot of the monolithic bullets have driving bands and have less bearing surface than conventional cup and core bulets. Barnes often recommends adding more powder to get their bullets up to the same pressure (velocity) as conventional bullets.

If you use the starting loads for similar bullet weights and work up in small increments you will be safe.