AR: 16" Gov't Profile vs 24" HBAR: Load Considerations


PDA






momchenr
August 5, 2010, 11:45 AM
I currently use an S&W MP15 for fun and zombie defense. I've been kicking around getting a 24" Varmint HBAR 1/8" twist upper for it for some time now from Model 1 Sales... just for benchrest-longrange stuff, and I'd like to get into the 75-grain pills. Right now my 1/9" keeps me around 62gr. I've done a lot of reading, but am just looking for general advice, I guess. The Model 1 is within my price range, and I'm not looking to tote this thing around - so I don't care about the weight factor at all.

Thing is, I reload all my .223, and I'm wondering if the increased barrel length, and by entension, velocity - is going to affect how I need to load. Will having a 24" bull in addition to a 16" gov't profile affect my loading stratgies, if I'm looking to take advantage of the increased length? Do my previous loads, if kept under maximum charge, have any potential for "bad pressure situations" in a higher-velocity 24" barrel? Has anyone heard anything terrible about Model 1's 24" 1/8" HBAR product(s)?

If you enjoyed reading about "AR: 16" Gov't Profile vs 24" HBAR: Load Considerations" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
cougar1717
August 5, 2010, 12:23 PM
If you work the load up using published reloading information, you do not need to change anything. There are no universal short barrel loads or long barrel loads, just loads that work better in a particular rifle. Please remember also that just because a gun has a longer barrel does not mean that it always has better accuracy than a shorter barrel.

MEHavey
August 5, 2010, 01:37 PM
I did not see a 1-in-8 variant in Colt's HBAR lineup (and they only have one 24" 'SS' model)

http://www.coltsmfg.com/products-c6-q9-Colt_Rifles.aspx

Where would you be getting the gun/barrel?

rcmodel
August 5, 2010, 01:53 PM
He said:
I've been kicking around getting a 24" Varmint HBAR 1/8" twist upper for it for some time now from Model 1 Sales...

But he didn't say it was a Colt HBAR.
Just an HBAR type upper from Model 1 Sales..

rc

momchenr
August 5, 2010, 01:57 PM
I must have my terminology wrong - I thought HBAR was a generic abbreviation for "Heavy Barrel" or "Bull Barrel." This was the item in question...

http://www.model1sales.com/index.cfm?fuseaction=category.display&category_id=264

I was going to get it with a plain aluminum free float tube, a 1/8" twist... etc. Just wanted to be sure that the extra length wouldn't change things in my reloading strategies too much - ie, case life, pressure considerations, etc. I had a feeling they wouldn't, but I don't really have anyone to ask or talk to about it within my circle of friends so I have to ask my stupid questions on here, I guess.

jmorris
August 5, 2010, 02:02 PM
I have a bunch of M1S uppers and they are a good buy. I feel the case capacity of the 223 isn't enough to get a lot of benefit from a 24. A 20 will do just fine. If you want to go further with a little bullet the 22-250 or swift are a better choice.

momchenr
August 5, 2010, 02:13 PM
So, you're saying that if benchrest shooting / long-range target is the game... a 24" doesn't have enough benefit over a 20"? Can you explain a little more, along with maybe links to data? I'm totally okay with the idea of a 24" - I don't plan on prowling around with this thing, just sitting there. A 20" is the same price as a 24" on M1S, so I'd have to actually "prefer" a 20" in order for it to make sense. Do you have time to elaborate?

jmorris
August 5, 2010, 04:56 PM
So, you're saying that if benchrest shooting / long-range target is the game... a 24" doesn't have enough benefit over a 20"? Can you explain a little more, along with maybe links to data?

Not exactly. In .223 using factory ammunition you only see about 100fps increase velocity going from a 20” to a 24”, the case volume is small relative to more powerful .22‘s. At the ranges .223 is effective it just won’t make that much difference but does make the rifle less maneuverable.

Long range means different things to different people but I can tell you this the load you use at 600 yards will make much more difference that your barrel length. From shooting groups with different rifles and shooters on the same day with the same ammunition I found that:

The shooter has the most impact on group size.
The barrel manufacture seemed to be #2
We used the same lower and optic though.

FWIW .223 isn’t the best cartridge for benchrest competition nor is the AR the best platform. You might poke around here http://www.6mmbr.com/index.html

Here is a data link that shows longer barrel length does not necessarily mean more accuracy. http://www.accuratereloading.com/223sb.html

If you enjoyed reading about "AR: 16" Gov't Profile vs 24" HBAR: Load Considerations" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!