55g 223/556 bullet question

I got some supposedly 55g FMJBT bullets, but when i weigh them, they are weighing 1-1.3g light. So, they are 53.7 to 54g for the majority.

First time i've gotten bullets this far off of what they are ''supposed'' to be.

Should I alter my charge due to the lighter weight bullet?

A 55gr nominal weight bullet of 53.7gr actual weight is light by just under 1%. There's no practicable adjustment you could make.

Also consider that a scale can be off by that much.

If you calibrate your scale, it won't be off. I'd worry more about inconsistent weights, rather than all the bullets being light by the same amount. If he bullets are consistently light, then just bump your charge up a little, in order to get the velocities that you want. Won't take much.

Thanks! They do vary wildly. Out of 10, 5 or 6 may be 54.3, but 3 may be 53.5, or 53.6. 2 may be 53.8. So out of 100, i could get possibly 1/2 of them below 54.0.

My Hornady's usually run +/- .1. These are +/- 1.0 - 1.5...

Just didn't want wildly variations with the Chrony, working up loads with light bullets. (Digital Scales, that are calibrated), so no worries there. But, i believe i'll weigh each bullet and group them into weight classes so i get consistant readings. Just wasn't sure if i should "reduce or advance" the load because of the lighter bullets.

FMJ-BT military style bullets are the cheapest and most inconstant bullets you can buy.

But the bearing surface for a 55 grain FMJ-BT that weighs 1.3 less is still the same bearing surface, and the same pressure.

Don't worry about it.
Use 55 grain data.

rc

I would agree with your plan to weigh each, sort your loads, and maintain a log of each load, how they perform Chrony, accuracy, all the usual stuff.

If you are concerned with the QA of the bullets, shop around, there are lots of sources.

Good Luck
Dan

Night time comfort,
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Colt LE, 5.56mm, Quad Rails, Laser, 150 Lumen Light, 8 Magpull 30’s, a Henry 45LC Mares Leg, a Winchester Model 94, 3030, a H&K MP5, a Sig Sauer Mosquito, Savage 17HMR, Sweet 17 Scope. A Remington .243, a Beretta 92FS, a CZ 75 (Original) Still a Tack Driver), And about 20 others, too many to list.

Reloading all but the 17, 22LR and the 12

...i believe i'll weigh each bullet and group them into weight classes so i get consistant readings

Waste of time. You could have them blessed by the pope and they’ll still be FMJ’s. If you need better accuracy, go with match bullets.

Ive had factory bullets the same way. If they are supposed to be a certain grain than use that grain for your loads. If its a big jump on your bullet weight then i would use different grain powder. I would say +/- 2 grain.