Barrel length, 45 Colt, and H110

[Naphtali]

Shopping for a lever action rifle to pair with my Freedom Arms Model 97 45 Colt, I discovered a nuance about which I know next to nothing. One of my revolver loads uses a 300-grain SWC-GC propelled by H110. While a stiff "hunting" load, it is not out of the ordinary for a revolver that is safe with pressures acceptable in Ruger Blackhawks. And whichever lever action I acquire will also accept the same 45 Colt/300/H110 load without issues.

H110 is not exactly a handgun powder, nor is it - developed for 30 M1 Carbine - exactly a rifle powder. Is there a barrel length beyond which no significant velocity gain occurs? I mean H110 was developed to achieve ballistics from 18-inch barrels using 110-grain 30-caliber bullets. From 18-20 inch 45 Colt carbine barrels, I expect substantial velocity gain over a 5.5-inch revolver barrel. But barrels of 30 inches are available in lever action 45 Colt rifles. I suspect somewhere between 18 and 30 inches H110 exhausts its potential to significantly improve velocity.

Is there a formula that identifies H110's maximum optimum barrel length? Or, perhaps, some empirical method that avoids using several test rifles in several barrel lengths, plus huge amount of ammunition to create a graph that shows where maximum optimum barrel length is?

[DougGuy]

Using QuickLoad, Lee C452-300-RF boolit over 23.5gr H110 with 27,773psi maximum pressure, 1.6" COA shows that H110 never fully burns 100% even in a 36" barrel. The velocity gains are still adding up as barrel length is added.

This load for instance in a 7 1/2" revolver where it is measured from the breech face to be 9.125" shows a velocity of 1347fps with 82.15% of the powder burned for a Ballistic Efficiency rating of only 26.2%.

A 14" barrel shows a velocity of 1471, with 86.67% powder burn, 31.2% Ballistic Efficiency.

An 18" barrel goes 1537, 88.81% at 34.1%,

A 20" barrel goes 1563, 89.61%, at 35.3%

A 24" barrel goes 1607, 90.88%, at 37.3%

A 30" barrel goes 1658, 92.25% at 39.7%

A 36" barrel goes 1698, 93.23% at 41.6%

A 48" barrel goes 1756, 94.57%, at 44.5%

A 60" barrel goes 1799, 95.44% at 46.7%

An 84" barrel goes 1859fps, 96.55% powder burned at a Ballistic Efficiency of 49.9%

Now this is in QuickLoad, which merely predicts what the numbers may be using the math within the program so this is just speculation based on scientific principle and known characteristics of the powder.

According to the numbers, there really is NO optimum barrel length with H110 and the Lee 300gr.

You would eventually arrive at barrel length where powder was as close to 100% burned as it will get and as barrel length was added, a point where the velocity began to fall off would be considered the barrel length required for 100% powder burn, which is of no use in determining optimum barrel length, the two numbers do not have any significant meaning when using H110.

Since there are a LOT of variables not considered in QuickLoad one can only use QuickLoad to look at the mathematical possibilities and not real world data that would take into account barrel friction, pressure in the barrel ahead of the boolit, etc..

There is also the question of what is the optimum barrel length for the SHOOTER? Competition at short ranges would dictate a trapper length carbine, hunting at longer ranges would dictate the longest barrel the hunter can realistically carry into the hunting area.

For all practical purposes, a 20" carbine will be hard to beat as it handles easily and will take any game on the planet with the load you mentioned, a 24" rifle has a slight advantage in velocity and may be more accurate at 100+yds but does not handle as easily as a carbine.

The boolit itself is the limiting factor here. The 300 is a 100yd boolit, and can be quite inaccurate beyond 100yds so to truthfully answer your question, knowing the optimum barrel length for H110 is a moot point. The optimum barrel length for the particular boolit would be the barrel that gives the most accuracy at which distance this boolit is still effective.

[OS OK]

That's pretty interesting, don't have that software, never used or discussed it...always used the load tables and a good old SWAG to figure these things...low tech for sure.
But...just for giggles, could you run that software again using Unique as the powder? He want's a stiff load, so perhaps start with 9 grains...or, I have no Idea...my .45 Colt is a wimpy Colt so I can't go there, but, My pard does this hot stuff all the time in his hand cannon Ruger.

Thanks...charlie

[DougGuy]

Unique and heavy boolits do NOT dance well. John Linebaugh gives some Unique data that he personally has used but I personally will not use over 10.0gr Unique in .45 Colt cases with ANY boolit. Unique at 10.0gr and above can be spiky and unpredictable. With 250-260gr boolits, when you need more than about 9.5gr Unique, it's time to switch powders for something a little slower burning.

QL shows 10.0gr under the Lee C452-300-RF produces only 1120fps, while pushing the pressure up to 28.368psi. This is using 320gr as the boolit weight as this is what mine weigh checked and lubed.

[OS OK]

So...that tells me that we should be looking into a fast 'stick or extruded' powder with built in burn control by design. It sounds like you been down this road so what do you suggest using that program as the reasoning basis?

**added, The above test, was that short pistol type barrel test?
Also, since most of us have a lever gun, my questions are more along the lines of using that one hot load between the SAA Ruger and a short bbl'd carbine...get my drift? Not necessarily the hottest load but a load that is fairly efficient in both, yet definitely considered stiff.

[DougGuy]

Stick powders are for bottleneck cases. For magnum pistol you want ball or spherical. Slow burning. Shotgun powders work in magnum pistol.

Max loads in the big bores call for H110 as it has the best burn rate to fling heavy for caliber booolits. 23.5gr is about the most you would want to go in a large framed Ruger under the 300gr RF and this is with it seated out long in the lower crimp groove. In a 7 1/2" barrel you would net 1340fps at the Ruger's max allowable 30,000psi, this load produces 29,930psi.

18.0gr A2400 would net 1275fps at a little over 28kpsi.

23.0gr LilGun would net 1372 at 28,895psi but is known to burn hot enough to erode forcing cones in the FA revolvers which are loaded CONSIDERABLY hotter than the max Ruger loads.

2400 and LilGun can be safely downloaded into the 85% power level of the Ruger, this is where I load mine for hunting and basically everything else. H110 SHOULD NOT be downloaded below recommended starting weights which don't quote me but I think 20.5gr is the starting charge? I got tired of splitting 36" of seasoned oak firewood with H110.

[OS OK]

I think what I'm describing is more along the lines of a 'Practical Stiff' type load where you don't necessarily wring every last FPS out of the powder but you get a load that is not up there next to the maximum levels...that just gives me the creeps.
It's also interesting how you showed the progressively longer barrels and the burn efficiency levels increasing, can you show that with the 2400?
My pard uses mostly the 2400 and thinks it is actually the answer to this dual type stiff load.

[DougGuy]

Well, we already steered the thread from what the OP wanted to ask so let's get back on track.

The velocity gains with 2400 fall off quicker in the longer barrels.

[OS OK]

Sorry for the diversion OP...in the wee hours of the morning I don't think of these things. These threads seem more like casual conversations instead...still, sorry to butt in and thanks Doug.

charlie

[w5pv]

Thanks for the discussion on the loads

[fecmech]

I have no experience with the.45 Colt cartridge but quite a lot with .357 in rifles and pistols. When using H110/296 in 20-24" .357 rifle barrels you gain about 400 FPS over 6" pistol velocities. I would expect very similar results in the .45 Colt.

[RPRNY]

You will gain roughly 40-50 fps per barrel inch above 6" in a rifle. While you may continue to gain at that level beyond 20", you begin to lose in the handiness category. In addition to which, at over 1800 fps, you are moving into the dark arts area of cast bullet shooting. While there are practitioners who will tell you all about their success in shooting cast bullets over 2000 fps, even they are unlikely to suggest that the same bullet that you would want to use in your revolver will work well at that speed, let alone the discussion of terminal ballistics.

300 grs of appropriate BHN doesn't need to be going fast to do a whole lot of damage. If you are happy with the H110 300 gr load in your revolver, my suggestion is that you will be extremely happy with it in a 16" uber-handy lever gun. And if you need the extra magazine capacity, similarly happy with a 20" barrel. At 16" you can expect something in the range of 400 - 500 fps faster than your revolver. At 20" the theoretical range is 560 - 700 fps faster (although in reality I'd expect less). I would suggest 16"-18" on barrel length.

[KCSO]

There is very little difference between a 20" Rossi Carbine and a 24+ rifle with the 45 and H110. IIRR it was like 50 fps and you can get that much from gun to gun. You will whoop up the velocity by at least 400 fps. You might want to check out Pet Loads by Waters as he has a good heavy 45 load section.

[TXGunNut]

I use a similar load (296) in my RBH and have shot a few in my 94 Trapper. Been quite awhile since I fired the Trapper but I can assure you the loads were much more pleasant to shoot in the Trapper than in the RBH. No pressure signs or other bad behavior.

[MostlyLeverGuns]

Longer barrels have less muzzle blast, provide a longer sight radius, easier to shoot more accurately, more pleasant to shoot for fun. For utility rifles, Horseback - 20" to 22" isn't too bad. In and out of vehicles even 20" seems long. With handgun cartridges the effect of barrel length on velocity doesn't make much difference for expected usage.

[Naphtali]

Wow! Great stuff here. What appears to be better facet on which to choose is barrel length that allows me and my [usual] sight system to be 8 MOA ± 4 MOA from point of aim. This reads more complicated than it is. I have a point of aim. I want to be able to hit within 4 inches of that point of aim. But the total group size for [many] 5-shot groups can be as large as 8 inches. There. Easier to visualize.

[Tackleberry41]

I tried the same loads in my blackhawk as my rossi 92. 240gr XTP mag w 22gr of W296 gets about 1720fps in the rossi, it drops to 1200 in the blackhawk, with a completely unacceptable muzzle blast. So I have rifle loads and pistol loads. The pistol ones work fine in the rifle, w a 200fps or so boost. But what works good in the rifle, sucks in the pistol. I switched to faster powder like unique in my pistol.

[OS OK]

Naphtali...

The quality of your ammo is not always to blame when you have a problem getting it to come in tight...sometimes we as shooters are doing something or several things unknowingly...use these charts to analyze your targets, when you hit in tight a few times then a few of them start loosely grouping together somewhere else, you might explain and correct the problem with this pair of charts.

Sometimes I heel, sometimes I have too little trigger finger pad centered on the trigger...healing has been my hardest bad habit to break, I don't do it consciously...It's more like I become a 'spastic' at times in that microsecond before sending the round in the 1911.

charlie