My first .223 reloads. Question about group, charge weight, bullet drop due to temp

[Monmouth]

Last week, I reloaded my first ammo and took 3 shots down range (first one single in a mag, loaded 2 in a mag and fired). I was cautious because this was my very first time reloading ammo and just in case I really screwed up in the process and it blew up. I have the Lee Classic Turret and dies.

Please note the following data:

- New Winchester .223 brass out of the bag. I Full case size and then chamfered each one.
- .55 gr Montana Gold's
- Remington 7.5 primer
- BL-C powder
- 46-47 degree temp
- 70% humidy (not sure on accuracy)
- 35 barometer (used my phone app, not sure if this is correct)
- 8 mph wind South Southeast (not sure on app accuracy, but seemed calm)
- I don't have a chronograph, yet.

Range - 100 yards
Rifle - built my own AR-15 with a 16" Daniel Defense barrell with 1/7 twist
Scope - SWFA 10x42 (thank you Snipershide for the reviews, love the scope)
Rifle rested on the Dick's shooting bag with the little bag under the stock

I read about ladder testing and this is the group I achieved with the following charges:
- 24.50 gr
- 25.00 gr
- 25.25 gr
- 25.50 gr
- Pinky finger for scale is 1 cm.

No pressure signs or primer cratering at all. Would you recommend that this load range is satisfactory, go with an even 25.00 gr of powder, and load quantities of it? Do I need more testing? Please help.

Lastly, I zero'ed my scope last month with American Eagle 55 gr ammo in 23 degree temps with 15-20+ wind. My aim was dead on today, but would an increase in 20-23 degrees cause the bullet to drop this much? I initially shot with the same American Eagle ammo and had the same bulllet drop. As the day progressed and the temp dropped down 10-15 degrees, bullets started to rise back up.

 

[Monmouth]

I suck, pic didn't upload in original post.

 

[nso123]

There is not always an easy explanation for one load having a different point of impact from another. Chances are since your loads are toward the bottom end of the load range, the factory ammo was a little hotter, which might explain the impact shift. Was this group from the 4 different powder charges you listed, or is it a group of 1 of the listed charges?

 

[Monmouth]

There is not always an easy explanation for one load having a different point of impact from another. Chances are since your loads are toward the bottom end of the load range, the factory ammo was a little hotter, which might explain the impact shift. Was this group from the 4 different powder charges you listed, or is it a group of 1 of the listed charges?

The group is one from each charge. Is it bad that my loads are at the bottom end of the range or should I work up to the higher end?

 

[milo 2.0]

You really can't say it's bullet drop, different loads will impact the target different. You really didn't run a ladder test in the true sense.
I'd load 3-5 of each of the charges listed and shoot groups. Running them over a chrono wil help decide what powder charge you want.

For what you did there, I'd say the gun is gonna shoot!

Oops, just read your second post. At 25.5 gr of BL-C2 you reaching the max recommended charge, this is where a chrono helps.

 

[Monmouth]

Thank you Milo,

Ok, I will load 5 of each group, head back to the range next weekend, and shoot groups. Could you explain how the chrono will help decide the powder charge because I thought group size dictates powder charge?

Sorry, I'm very new to this.

 

[milo 2.0]

Thank you Milo,

Ok, I will load 5 of each group, head back to the range next weekend, and shoot groups. Could you explain how the chrono will help decide the powder charge because I thought group size dictates powder charge?

Sorry, I'm very new to this.

Yes group size or accuracy trumps speed, but if your most accurate group is only going 2400fps, then you might want more powder, if you do the testing simutanously you can kill two birds with one stone.

 

[Monmouth]

Yes group size or accuracy trumps speed, but if your most accurate group is only going 2400fps, then you might want more powder, if you do the testing simutanously you can kill two birds with one stone.

Understood,

Have to get a chronograph. Quick question, after I do the 5 shot group test with each load, should I then push it further by taking the 2 best load groupings and then shoot shoot those with a 5 shot group at 200 yards? Would the lack of speed start to show at 200 yards by the groups opening up more than it should?

 

[milo 2.0]

If you're charges are the same, impact shouldn't vary because of speed. By all means shoot at 200, it's a better test anyday.

 

[DieselWSM]

For the most part, dont build your loads around speed (IMO). If you find a load that shoots consistently tight groups (i.e. sub MOA groups), run with it. I agree 100% with Milo that if your load is running way slow then yes, work up a higher load. The pic you posted is an outstanding group for a .55gr bullet out of a 1:7 twist. My ARs are all 1:7 twist and will not shoot better than 2" @ 100. Your barrel really likes 77gr bullets as well.

I guess I am a little confused about your initial post...were your impact deviations from factory v. reload ammo or factory v. factory? Zeroing a rifle in 20+ mph wind can prove a little difficult, especially a bullet with that much susceptibility to wind. I am not that familiar with BL-C powder and it may deviate with temperature extremes, again, not that familiar. A powder like AR Comp is "supposed" to be unaffected by temperature.

Reloading manuals are going to give your max loads with a safety factor, I AM NOT telling you to go over book max since there is an inherent danger and with you being an admitted new reloader I would get a little more comfortable with things. I load over book max by 2 full grains on my .308 but that is a different animal all together.

Seems like you are doing pretty good and off to a great start. The speeds in the reloading manuals are never correct in my experience but it will give you a good idea of where your bullet speeds are. Again, shoot what works and try not to second guess your bullets...they dont lie.

 

[Monmouth]

Went back to the range today, but only brought 10 rounds with 25 gr and 10 rounds with 25.3 gr. Shot a 5 round string with each weight at 100 yards and 200 yards. I'm going with the 25 gr load as it performed best at 200 yards (at 100 yards, it was close with 25gr with the tightest groups).

Thank you for the advice and help. Going to invest in a chrono now.