Don't understand treating copper plated like lead bullets

[dsv424]

I see a lot of people saying to treat copper plated bullets like lead when working up a load. But the other day when I ordered some 9mm Ranier copper plated bullets it said to keep the velocity below 1500 fps. Well all of my recipes for 9mm FMJ are under 1500 fps so I would assume I can use these recipes for the copper plated rounds. If I were to load them as I do lead bullets the velocity would be around 900 to 1100 fps. I would think that as long as I adhere to the less than 1500 fps I could use FMJ recipes. What am I missing here?

[Alpo]

http://www.rainierballistics.com/mainframe.htm Click on "loading data". Rainier says to load 'em like lead.

http://www.berrysmfg.com/faq.aspx?q=9&c=1 Berry's says load "low to midrange jacketed" loads

[medalguy]

The precaution applies to rifle as well as pistol bullets. Yes most handgun loads are under 1200 fps but if you go much over that the barrel rifling will simply cut the plating and the lead core will go downrange amid a bunch of copper shreds. The target will look like swiss cheese. Keep in mind the plating is only a two or three thousandths of an inch thick, whereas a jacketed bullet may be twenty thousandths of an inch. I don't know the exact thickness but jacketed is MUCH thicker than plated.

As long as you keep the velocity down you should have no problems. I load 9mm to about 1100 fps and I've never seen a shredded bullet (yet).

However if you intend to load for rifle for target or plinking, then you need to be very careful of the velocity. Don't load to 2700 fps and expect to do much with the bullet.

[res45]

As long as you keep the velocity down you should have no problems. I load 9mm to about 1100 fps and I've never seen a shredded bullet (yet).

+1 besides all the info stated above,plated bullets are a compromise between lead and jacketed bullets,no only price wise but with the leading problems some people experience. As long as you keep the plated pistol bullets under 1200 fps. and the respective rifle bullets under 1700 fps. you will have no problems

[JLA]

to put it simple... They mean plated bullets behave more like lead bullets. They should be developed with lead load data because the pressures and velocities generated will be more applicable to your plated bullets. If you use jacketed bullet data your velocities will be much lower with the plated bullets... The plated bullet companies are just trying to prevent confusion.

[dsv424]

Thx everyone for the explanation, but this raises another question(sorry for being a pest about this). So what your saying is that if I had a 124 g. FMJ and a 124 g. copper plated and loaded them with the exact amount of powder the FMJ one would produce a higher velocity. Why is this if they both weigh the same and are shaped the same?

[wpage]

Drag coefficients.

[TheGunClinger]

I loaded about 250 rounds off .44 mag with 23g H110 and 240 gr Ranier hp. I mistakenly thought that they were FMJ and loaded accordingly. Now I am a bit nervous about these loads. There isnt any data on 240 gr lead with that powder. If I compare other powders it seems like the lead bullets take More powder. Bue dot the load for fmj is 13.1 with a velocity of 1380 fps but with a lead bullet the load is 15.2 gr ith a velocity of 1475 fps. My question is my .44 load going to be safe? I have shot a bunch of them before I realized my error and they all worked fine.

[GMFWoodchuck]

Perhaps they want the speeds reduced to prevent the bullets from breaking apart against a steel barrier. It wouldn't mean much outdoors, but if you're shooting range/club is indoors then it would matter as the lead would be in the air if they broke up....

[JLA]

Originally Posted by wpage

Drag coefficients.

Not entirely true but it does apply somewhat. Its because the copper jacketed bullets are harder and produce more pressure in a given cartridge. thats why you usually get more velocity with the same powder using jacketed. You can use jacketed data with lead but never substitute lead data for jacketed ESPECIALLY toward maximum charge you could end up with a busted gun... just be safe and try to stick with specific data for the bullets you use

[JLA]

Originally Posted by TheGunClinger

I loaded about 250 rounds off .44 mag with 23g H110 and 240 gr Ranier hp. I mistakenly thought that they were FMJ and loaded accordingly. Now I am a bit nervous about these loads. There isnt any data on 240 gr lead with that powder. If I compare other powders it seems like the lead bullets take More powder. Bue dot the load for fmj is 13.1 with a velocity of 1380 fps but with a lead bullet the load is 15.2 gr ith a velocity of 1475 fps. My question is my .44 load going to be safe? I have shot a bunch of them before I realized my error and they all worked fine.

Your loads will be ok. Now had you loaded 240 gr XTPs under a maximum (for lead) load of 26 gr of H110 then Id say pull the bullets and start over. but you goofed in the right direction My only other advice is to try not to shoot yourself in the foot since you are a new england fan and all

[DWARREN123]

Many factors here. The gun and what shape it is in, type of rifling, powder type and amount. I run plated 40 S&W rather warm but have never had a problem.

[TheGunClinger]

Originally Posted by JLA

Your loads will be ok. Now had you loaded 240 gr XTPs under a maximum (for lead) load of 26 gr of H110 then Id say pull the bullets and start over. but you goofed in the right direction My only other advice is to try not to shoot yourself in the foot since you are a new england fan and all

Thanks for the first bit of info. Makes me feel better. As for the last bit Ow! That hurts. We really blew it big time. Sorry dsv424 for getting off track.

[JLA]

Originally Posted by TheGunClinger

Thanks for the first bit of info. Makes me feel better. As for the last bit Ow! That hurts. We really blew it big time. Sorry dsv424 for getting off track.

Yeah, Cowboys choked at green bay yesterday too Was a rather boring game... panalty after penalty after penalty, sheesh i wish they wouldnt pay these guys for screwing up

[38 special]

Maybe the copper plating is Very thin or the bond between the lead and jacket is quite weak. Just a thought.

[dsv424]

but never substitute lead data for jacketed ESPECIALLY toward maximum charge you could end up with a busted gun...

I'm confused by that statement JLA. I would have thought doing this would just be a light load for a jacketed bullet. Although I would never take this route, I might go the other way (substituting jacketed data for lead data and use the low end jacket data). I'm missing something here, could you please explain. Thx

[Claude Clay]

If you use jacketed bullet data your velocities will be much lower with the plated bullets...

cause the softer lead bullet will expand more in the barrel thus engaging more of the lands surface.
more friction= less velocity

more friction also goes to higher pressure.
less friction cause the case of a FMJ has a brinel of +35 compared to a ~12 to 18 for plated.
even though a FMJ has more powder the pressure is not much greater cause the
bullet is more slippery and there are more blow by gasses than a lead round.

recover a lead or plated bullet and a FMJ
note the deeper cuts made by the lands on the lead or plated bullet.
the lead bullet may also expand to touch the groves and there by,
since it can not expand any more, it lengthens.
this deformation takes energy.
less energy=less velocity
also since it has sealed the expanding gasses behind it,
the pressure remains high, unlike the FMJ which allows for blow-by gasses.
so, once the bullet is 'sealed' the pressure remains high thus helping the bullet along.
but a pistol is too short barreled for the gain to out weight the cost.

there is more to this.....
ain't there always??

bottom line--Follow The Manual
and cross reference. have 2 or more manuals.
do not get creative when reloading.

[dsv424]

Claude thanks for that enlightening bit of info. That was very helpful in understanding whats going on as different styles of bullets travel down the barrel. I really appreciate helping me understand this. Although I have six major reloading manuals and 8 of the little booklets I don't think I have every heard it explained as such. But I might need to do a "bit" more reading in the front portion of my manuals. Thanks again.

[TheGunClinger]

Read the WHOLE manual. I read it and read it and still I have questions. This forum is the best place to acquire the accumalated knowledge of experts who have been there done that.

[GMFWoodchuck]

I still think it's to reduce bullet break up against a steel target.....