.223 loads for 16inch barrel questions

Status
Not open for further replies.
H

hub

Member
Joined
Nov 14, 2005
Messages
482
Location
memphis, indiana
OK, I'm am new to reloading and looking for some powder advice. I have a varmint AR that I'm starting to reload for that has a 16in heavy barrel and a 1-9 twist. It shoots pretty good but I'm wondering how much velocity I'm actually loosing with the short barrel and if I could make some custom loads to make up the difference.

I have several reloading books now but I believe all use 20-26 inch test barrels in their data. I'm guessing the drop in velocity is from not getting a full powder burn in 16 inches, right? Is it possible to use a faster burning powder to get a complete burn in 16 inches and if so what powders would you recommend.

I know the printed velocity in the reloading manual is not always right on but considering the difference in barrel length that I am using will the printed velocities be way off from what I will be getting with the same loads?

Is there a good way to estimate what kind of velocity loss I will experience with each powder using a shorter barrel without a chronograph? Formula, software programs?
 
Is it possible to use a faster burning powder to get a complete burn in 16 inches and if so what powders would you recommend.
Click to expand...
Only a chronograph would know. Fast powders gives less fps then slower powders if you look at Sierra data here. See the powders in the 3100 fps class, they will give you the highest velocity. http://www.6mmbr.com/223Rem.html One inch of barrel is about 35 to 50 fps. Burn rate of powders here http://www.hodgdon.com/burn-rate.html My data for a 14.5" 5.56mm chamber barrel with a load of IMR 4198 @ 21.5gr, 55gr Hornady FMJ give 2766 fps over the screens. When compared to Sierra data with a 20" barrel shows i lose about 40 fps per 1" of barrel.
 
Last edited:
Whatever powder gives the highest velocity in a long barrel will also give the highest velocity in a short barrel.

That can be proven if you look at a loading manual that includes chapters for both rifles and Contender handguns.

Lyman #49 lists a 55 grain bullet over 27.0 grains H335 as the fastest load in a 10" pistol at 2,850 FPS.

It is also the fastest of the powders tested in the pistol under the rifle section using the same 27.0 grain load in a 20" barrel at 3,270 FPS.

Varget & AA-2015 were the two powders giving the highest velocity in the rifle section, and you could expect the same in a 10" Contender, or 16" carbine.

Faster powders reach maximum pressure too soon to produce top velocity in any barrel length.

Here is a link to a good test on how much barrel length effects velocity in the .223.
http://www.accuratereloading.com/223sb.html

rc
 
There are several good questions here and since nobody has answered I will try. First off, I wouldn't get too hung up on getting the absolute highest velocity out of your reloads. You primarily want them to be accurate and traveling fast enough at your personal maximum range to have the effect you want. Depending on bullet type, that might mean expand, yaw, fragment, whatever.

I as understand it, longer barrels may actually produce lower velocities under certain conditions. As you eluded to above, once the pressure from the powder burn falls off and the bullet still has to travel a considerable distance through the friction of the rifling, you may lose velocity.

The almighty Varget powder is what everyone likes for .223, but it's tough to find. The Bass Pro near you has a ton of BCL-2 which would likely be a good alternative and available without extra shipping expenses (I know it's there as I saw it a few days ago). I have read that people have produced very accurate loads using that powder.

BTW, I really like Memphis, IN. It's a great place to ride a motorcycle.

Edited to add - You guys type fast, ignore the first sentence!
 
Not even true in very long bolt-action match rifles.

It is true in .22 RF in barrels over 26" long though.

Not a factor at all in center-fire calibers and manageable barrel lengths up to 28" or more.

rc
 
243 - I think you may well be right in regards to .223. I just remember reading an article in a recent American Handgunner about .44 Mag loads in pistols vs. rifles and often the rifles actually produced lower velocities (I'm guessing the powders were much faster than those for .223). As mentioned above, I'm not sure there is any way to know what the results will be without doing the chrono work.
 
You fellas have this mistaken notion that "burn rate" relates to the entire length of the barrel.

but rather burnrate relates to the first 3 or 4 inches of bullet travel after which point all the propellant is consumed and the bullet is now being driven forward by the several thousand PSI of expanding gas that was produced when the powder conflagrated.

Too slow a powder and full chamber pressure cannot be reached because the bullet outruns the powders ability to change to gas. So after a point you need more powder than can psychically fit in the case

too fast a powder and the bullet cannot get out of the way fast enough and chamber pressure spikes. At which point you must use less powder. less powder = a lower volume of gas and therefore lower pressure pushing on the base of the bullet resulting in lower muzzle velocities in ANY barrel length

This is why you always want to use the slowest powder that the cartridge can actually make use of. This would be a propellant that can reach max chamber pressure AND have the highest load densities (IE a case full)


243 - I think you may well be right in regards to .223. I just remember reading an article in a recent American Handgunner about .44 Mag loads in pistols vs. rifles and often the rifles actually produced lower velocities (I'm guessing the powders were much faster than those for .223). As mentioned above, I'm not sure there is any way to know what the results will be without doing the chrono work.
Click to expand...

You MIGHT see this with loads that burn cmall quantities of FAST powders like found in cowboy action loads. But if you burn case fulls of ww296-H110 you'll not find a handgun outperforming a rifle in any bbl length under 25" or more. Many calculations put the point of no gain for bottle necked rifle cartridges at close to a 50" bbl
 
recent American Handgunner about .44 Mag loads in pistols vs. rifles
Click to expand...
I didn't read the artical, but again, looking at a decent reloading manual with rifle & pistol chapters for the same caliber will prove that wrong.

In the .44 Mag example, the fastest 240 grain load in a 4" pistol is 1,233 FPS.
The same exact load in a 20" carbine is 1,745 FPS.

Small capacity pistol calibers like 9mm and .45 ACP using fast powder can run out of steam in a longer rifle barrel.
But the .44 Mag holds enough slow burning powder to just get faster in a rifle.

rc
 
I'm loading a 55gr Sierra sp & 23 grains of Reloder 10X using using Alliant's data. I have not shot it over a chronograph yet, but it is very accurate out of my 16" Heavy barrel DPMS. It is listed at 3159 FPS with out any barrel size.

Jimmy K
 
Thanks everyone I really appreciate all your input. Like I said I'm pretty new to reloading metallic cartridges and I'm trying to get a grip on use of different types of powders and when and how they are to be used. Thanks for the links 243winxb looks like I've got some research to do.

Too slow a powder and full chamber pressure cannot be reached because the bullet outruns the powders ability to change to gas. So after a point you need more powder than can psychically fit in the case

too fast a powder and the bullet cannot get out of the way fast enough and chamber pressure spikes. At which point you must use less powder. less powder = a lower volume of gas and therefore lower pressure pushing on the base of the bullet resulting in lower muzzle velocities in ANY barrel length
Click to expand...

As poorly as I worded the question, that is exactly the type of answer I was looking for.
 
Whatever powder gives the highest velocity in a long barrel will also give the highest velocity in a short barrel.

That can be proven if you look at a loading manual that includes chapters for both rifles and Contender handguns.
Click to expand...
Thanks rcmodel I never even thought about looking at any info on the contender's.
 
Five of Clubs thanks for the info regarding BLC-2. I was at Bass Pro a few days ago looking at powder too and that's when these questions popped in my head. I seen they had some h335 and a few others, but wasent sure which way to go. I've got a few gift certificates for Christmas and that will be on the list. Do you know if they have primers too?

Also if you like riding in this area I'll give you another suggestion. Just past Memphis in Henryville the exit is S.R. 160. It is great for bike riding. It starts in Charlestown between Mcdonalds and Jayc and goes all the way to Salem. I used to ride it all the time, it's up downs and sweeping curves the whole way. It's a nicely paved road and the only downside is that there is no shoulders just a ditch that is usually pretty deep.
 
Jimmy K. my rifle is a heavy barrel DPMS too so I might give the sierra's and 10x a try sometime. I have some of Midway's Dogtown 50gr sp on hand right now so that's what I will be using this time in Winchester brass. Still not sure about powder or primers yet.
 
I've been using BL-C(2) and 55FMJ bullets in a 16" AR. Shoots very accurately (1" at 100" groups) but the muzzle velocity isn't up to some commercial 55FMJ ammo I've put through the rifle. I've chrono'd commercial 55FMJs (S&B) at about 3050 fps out of my 16" AR, while my BL-C(2) loads at published max of 27.5 grains don't go any faster than 2950 fps.

I've tried one or two other powders that I had around like IMR4895 (if I recall correctly) and got significantly slower bullet speeds than with my BL-C(2). The BL-C(2) loads still shoot accurately, though!
 
If you are shooting anything above 62 grain bullet, I doubt you will get optimal stability in a 16 inch barrel with a 1in 9 twist. Even at 55 grains I would go for max muzzle velocity to get optimal accuracy. Accuracy depends a great deal on spin rate, and spin rate is dependent on barrel twist and muzzle velocity. So go for the powder that maximizes muzzle velocity in your 16 inch barrel. Longer barrels give you a lot more to work with in terms of bullet weight and powder choice.

By the way, I know of no powder for use in a .223 that will result in lower velocity in a longer barrel. I also shoot 44 mag in handgun and rifle. I mostly use H110 in both firearms. Occasionally i use Unique in both. Unique is a handgun powder meaning it isn't a great choice for a rifle because of its very fast burn rate. Regardless, it will still give higher muzzle velocities in the 20 inch rifle barrel than the handgun, but not as much higher as H110. So some of the statements above to not mesh with my experience.
 
hub
I've used some FC(I know,all I could find), Winchester, LC 8? and some Magtech brass with that R10x load, all worked well so far. I also have some Reloder 15 loads with 60 gr Nosler partions to try on a deer or hog, but I ain't found any dumb enough to get in front of them. If it pretty weather here tomorrow, I'll try to fire some over the chrono and get back to you on the velocity. I don't have a scope on mine yet, I only have a red dot and can keep 10 shots in a 4" group at 100 yds. I think it'll do much better than that with a good scope. I'm new to the AR game, so I'm learning too, I've been reloading for over 40 yrs, but no AR.

Jimmy K
 
hub
Finally got around to running some of those loads over the chronograph today. Here goes:

55 gr. Sierra sp - 23.4 grs. Reloder 10x - Average 2860 FPS

Federal Factory 100 Bulk pak Walmart - 55 gr FMJ - Average 2893 FPS

60 gr Nosler Partion - 25.0 grs. Reloder 15- Average 2654 FPS

These are out of a DPMS Panther Sweet Sixteen HB .223 Chamber

I would have like to have got a little more FPS out of the 60 gr, but this was a first try for the RL15. The RL10X data is limited as it is a newer powder, maybe some one will come by with some more Data for it.
Just for kicks I shot my son's 270 WSM loaded with 60 grs of H4350 & 130 Sierra BT,it averaged 3092 FPS. It will put them under a nickel at 100 yds.

Jimmy K
 
Status
Not open for further replies.

Similar threads

Master Blaster
  • Locked
Relationship between Barrel Length, Burn rate, and velocity
Replies
12
Views
1K
rbernie
rbernie
1
  • Locked
What powder for a 16" .308 barrel?
Replies
7
Views
1K
db_tanker
D
M
  • Locked
9mm loads for 16" barrel?
Replies
12
Views
1K
ricciardelli
R
B
  • Locked
Fast vs slow burning powders for short barrel .223/5.56 loads
Replies
20
Views
14K
Toprudder
Toprudder
W
  • Locked
25-06 with 22" barrel. Powders?
Replies
12
Views
3K
uncle gheezer
U
Back
Top