Hornady 55gr FMJ BT vs 55gr SP BT (.223 Remington)

[Remington788]

Generally I load .223 using Hornady bulk 55gr FMJ boat tail bullets over Hodgdon CFE223 or IMR 4198. I've got good load data through my gun with these.
I also have a bulk bag of Hornady 55gr Soft Point bullets.
These would be fired from a Colt LE 6900 with an 18" 1/8 twist barrel.

Unfortunately, my range is closed, so I cannot do the usual trial and error load testing. So I am going to be loading a bunch without testing (not ideal, I know). According to my Lyman book, load data is virtually the same.
Does anyone have experience with these bullets?
Do you see a big difference in performance between them?

[abner13]

Check Hornady data. https://www.hornady.com/bullets/rifle/#!/

[Yellowfin]

I also like them and used Hornady's data for loading them. Been awhile since I did some last, might grab more of them. H335 is awesome powder for that weight class.

[Remington788]

I did not see any load data on the Hornady site, but the bullets are verrrrrrry similar. Both 55gr.
I used the same load I use for the FMJ. The load is well below the maximum.
IF, when the ranges reopen, they do not pattern well I will just pull the bullets and adjust the loads.
I was only able to make 50 before I ran out of powder anyway.
Must get to a store.

[cephas]

Performance? With AR velocities those SP's will blow a decent hole out the back of a varmint.
Friend told me.
When I started reloading you looked up your caliber, weight of bullet and looked at data presented. Most important was start at load and never exceed load. The usual procedure was to look at max load, decrease 10% and work up from there.
Today it seems every specific projectile has its own loading data. Just making an observation. Any data that increases safety is a good thing.
Looking at your two bullets, if I got the right ones, the FMJ length is 0.735 with a ballistic coefficient of 0.243.
The SP is 0.715 with a BC of 0.235. Pretty darn close. Your rifle will have to tell you the difference.
Chart for many bullets: http://www.shootforum.com/forum/bulletdb.html

[imashooter2]

Softpoints are intrinsically more accurate than FMJ due to the more consistent bases.

[GeneCC]

Generally I load .223 using Hornady bulk 55gr FMJ boat tail bullets over Hodgdon CFE223 or IMR 4198. I've got good load data through my gun with these.
I also have a bulk bag of Hornady 55gr Soft Point bullets.
These would be fired from a Colt LE 6900 with an 18" 1/8 twist barrel.

Unfortunately, my range is closed, so I cannot do the usual trial and error load testing. So I am going to be loading a bunch without testing (not ideal, I know). According to my Lyman book, load data is virtually the same.
Does anyone have experience with these bullets?
Do you see a big difference in performance between them?

I guess you're asking, "Do I need to develop new loads?"

I think you do. At least for the sake of accuracy.

Why? An SP isn't formed like an FMJ. Different mechanical history on forming the bullets. They probably will have slightly different lengths at the place on the ogive where your die touches the round. SPs tend to be less pointed than FMJs, yes?

I'd bet my paycheck that they will be very close loads.

Safety? I doubt it'll be a problem. I would probably redevelop just for the sake of curiosity.

[GeneCC]

There are several different SP bullets in .224 at 55 gr weights.

One has a cannelure. One does not.

We're getting into very fine points here. I'm tempted to say, "try it and see".

My sole safety concern is the combustion chamber space, which I define to be how much room in the cartridge for the powder to burn.

If the bullets are not displacing the same amount of space in the cartridge there may be a slight difference in the combustion chamber space. There may be pressure differences. Probably ain't much.

If this were my problem I'd do the following....


Take one of your FMJ bullets and an empty piece of brass. Find something soft to plug the primer hole. Felt or part of a paper towel. Weigh them.

Fill the case up to the mouth with water.

Seat the FMJ bullet in the case full of water. Allow for something to catch the water that squirts out of the flash hole. I'd go slow to keep things simple.

Weigh the combination. Subtract the difference between the finished round and the weights of the FMJ, plug and empty case. Divide the weight difference by the density of water.

This is the case capacity. Using water is a proven method of measuring case capacity.

Now try to duplicate that case capacity using one of the SP bullets. It'll take some time, but not as much as you might suspect.

You now have a seating setting that will duplicate the combustion, allowing for differences in engraving forces.


Alternative -

Measure the bullets. They will probably have different lengths.

Calculate the displaced volume of the bullet inside of the case. You do that by seating an FMJ round then measuring how much of it is inside of the case.

Now you have to measure the SP bullet, calculate how to seat it the same way.

[West Chester]

Everyone is being cautious for good reason.

Personally, I always work up accurate loads in each individual bullet, but would have zero problems stuffing a 55gr any style (FM, sp, hp, max, whatever) in a case using 55gr load data I have on hand. 25.0gr TAC