250 gr cowboy bullets in .45acp

[robertbank]

Anyone out there have any experience (Loads using Bulleye) loading thiese bullets in .45acp. I have some and just for fun am going to load up a few to see how they perform. The bullets I have are the same length as Lyman 230 gr RN cast bullets so seating depth is not an issue.

Take Care

Bob

[StarMetal]

Bob,

I fooled around with the RCBS cowboy and some Unique. I ran out of Bullseye and haven't replaced it. Out of my tuned 1911's it fed and shot well. It really shined out of my 45 Blackhawk with the acp cylinder. I forget the load I'll have to look, but it was stiff, reason why I shot the rest of them out of my Blackhawk.

Joe

[robertbank]

Hi Joe thanks for responding. I found some loads in my old Sharpe's Manual. Going with 4.1 gr Bullseye which is below max listed. I'll post my results and feelings about the load later this afternoon. Off to the range. Ah the pleasures of being retired.

Take Care

Bob

[dk17hmr]

I shoot a 260gr RNFP out of my 1911 loaded with 6.0gr of Unique its not a plinkin load shoots as good as anything else out of my Springfield. I made this load for bear hunting...not to take a bear with but to shoot one if I have to, I am going to carry it with my bow as a primary.

Velocity was 875fps when I checked it over our chorny.

[Bret4207]

Bob- Watch some of the load in Sharpes book. A load I thought I had transposed from another book or load sheet turned out to be spot on out of Sharpes Handloading book. It was way over loaded for Red Dot in a 38 case and I had posted it here. I ate crow on it and jsut found the load again the other day.

Just check to make sure it's at least reasonable by todays books or Quick load or something. Like Ackleys books, some of the loads appear very hot with todays components.

[robertbank]

You can say that again and be right twice! I used 4.1 gr of Bullseye under my 250 gr Cowboy bullet COL 1.887. OAL had to be that short for the round to chamber due to the meplat. I averaged 783 fps with this load which is way over what I need for shooting the games. A friend of mine and I are seeing if we can get down to 165 PF using heavy bullet on the assumption that we can achieve a lower felt recoil. Jury is out on it but it is fun tryiing. I am going down to 3.6 gr Bullseye and see what I get tomorrow.

Sharpe lists the 4.1 gr under 250 gr FMJ at 670 fps with pressure of 12,000. Well my lead goes 113 fps faster and primers were starting to flatten which indicates my pressures may hav been over 12,000.

Ah the joys of developing loads. Note FYI I am using my non-customized Norinco for this testing. No sense in donating my Para or my Custom Norinco to this project...

Take Care

Bob

[StarMetal]

Bob,

You noticed I didn't mention using Bullseye for my heavy bullet loads. Is there another slower powder you can use?

Joe

[slughammer]

... A friend of mine and I are seeing if we can get down to 165 PF using heavy bullet on the assumption that we can achieve a lower felt recoil. Jury is out on it but it is fun tryiing. I am going down to 3.6 gr Bullseye and see what I get tomorrow.


Your feelings on recoil implulse are an individual thing. Some like lighter boolits faster, some like heavy slow. It's all objective to you. Set up some standards and let the hit factor do the determination. Enjoy the experimenting. Next time start low and work up.

[robertbank]

slughammer - in the absence of info I thought I was!

Joe - I would have thought Unique would bave been a better powder for the heavier bullet. I am not interested in pounding out the bullet fast, just enough to make 165 PF which would mean achieving a velocity of 675+ fps. Going to drop back to 3.6 gr Bullseye and see what happens.

Sharpe lists 5 gr of Unique to achieve 730fps. Given my experience to date I'll drop that down to 4.5 and see what happens. I got 35 more bullets to chew on then I am down for awhile so gonna get it right quick...

Take Care Amigo

Bob

[StarMetal]

Bob,

What I was getting after wasn't pushing it fast. I was thinking of your requirement. I figured a slower powder would give a more gentle pressure peak thus softer recoil impulse. Bullseyes has a fast pressure peak and sharp recoil impulse. That's all. Yes you could load a reduced charge of Unique and since we're dealing with a small capacity here there's no worry of a reduced charge in a cavernous case.

Joe

[robertbank]

Joe

Yes when I first measured the 250 gr bullet and compared it to my 220 gr Lyman cast bullet I thought, hey I am good to go, forgetting of course the extra 30 grains had to come from somewhere and it was in the nose. I'll try both reduced loads tomorrow and report back. Aside from knocking over steel and punching paper I don't see much use for this load going forward as I am sure penetration would be an issue for hunting.

Take Care

Bob

[garandsrus]

Robertbank,


A friend of mine and I are seeing if we can get down to 165 PF using heavy bullet on the assumption that we can achieve a lower felt recoil. Jury is out on it but it is fun tryiing.

The new Dillon catalog that arrived today had an article on doing just what you described...

John

[Bret4207]

Bob- I have a feeling in Mr. Sharpe/Keith/Ackleys day there was a tendency for several things to be happening at once. I have no real proof, just a feeling. I think, my opinion only, that many of the guns they used had chambers and barrels that would be considered on the generous side today, brass that may have been a bit thinner than ours and their chronos may not have neen quite as accurate as ours. Add in the ego (even my Hero Elmer had one!) factor and some of those velocities and loads don't work out quite the same today as then.

Still, they did great work and it behooves all of us to read and re-read their books and articles for the info gathered there.

[robertbank]

garandsrus - That in part is what stirred this interest, that and just dumb curiosity. I sent Dillon a request for their catalogue and look forward to seeing what they have to say.

Tpr. Bret - I am a diciple of Phil Sharpe who indeed was a true pioneer for us handloaders. I agree with all you said regarding their data and equipment. Factor all of that into the likliehood that Bullseye as we know it may not be Bullseye as they knew it and we have a host of variables to deal with. As a young man I was a reader of Ackley and a student of Cooper's but have to admit never held Keith in much regard. After his passing, and as I aged I came to see and take a different view and now realize the qualities of the man. I agree the three had egos, don't we all, and I suspect there was more than a little of "oneupmanship" going on in their writings as they sought readership and a following.

Time to turn to my reloading. I'll report back later on the results.

Bob

[robertbank]

Well the whole purpose of this exerecise was to first find a load that would make IPSC/IDPA factor of 165 using 250 gr bullets. Some of said perceived recoil would be lighter. First the results. Listed velocites are the average of 10 rds fired over a F1 Chrony approx. 10" from the muzzle. Temperature varied from 14C to 16C. Gun was a Norinco A1 1911 with a 5" barrel. Bullet was a 250 gr RNFP bullet designed for ,45 Colt. COL was 1.887". Primers - Winchester LPP, Powder Bullseye

3 Gr. 522 fps PF 131
3.5 Gr. 625 fps PF 156
3.7 Gr. 716 fps PF 179
3.9 Gr. 735 fps PF 184
4.1 Gr. 783 fps PF 196

Other than the 3 gr load all loads really recoiled about the same with a progression as velocity increased. I have to admit I haven't been able to discern between a kick and a shove and a push when it comes to recoil but I can say this the 3.5 gr and 3.7 gr loads felt very similar to my standard game load of 5.3 gr Win 231 using a 200 gr LSWC. I have been told that different powders recoil differently when producing similar velocities using like bullets. I freely admit I do not have that capacity to confirm this though confess others may.

I did not test these loads for accuracy and I ran out of these bullets. Next time I am in Vancouver I'll pick up 500 of them and see what 3.6 gr produces in velocity and examin the bullets for accuracy.

All rounds cycled freely through my gun. Not sure what application one might use this bullet for but am open to suggestions. Certainly feeding is not an issue.

WARNING ! 4.1 gr of Bullseye using this combination did show signs of pressure with primers flatening. Personally I would not go further up the scale and won't load this load in the future.

Take Care

Bob

[StarMetal]

Bob,

It's like this kinda. An M16 has a gas port of a certain size up the barrel. It was designed to use certain powders where the port pressure would be what they wanted to bleed off a proper amount of gas to work the action. Usually the port was made larger then needed and the action actually takes a beating. Anyways, changing the port size or location, or powder type, changed the way the action cycled and the recoil. In semi auto pistols we can only change the powder speed and bullet weight. I can tell a big difference in recoil in a semi auto by using fast powders and slow ones. Sometimes a fast powder is so fast it doesn't have enough oomph and time to cycle the action completely. Fast powder too, to me, have what I call a sharp recoil, I guess a better way to say that is the recoil is sharp and abrupt. Slow powders, unless max loads, don't have that sharpness and the recoil seems spread out. It will be interesting to see what reduced charges of slower powder do to your load and recoil, if you choose to try them. If you do report what you notice different.

Joe

[Ricochet]

In a 1911, the pressure curve can't affect the recoil sensation, only the total momentum of the bullet and powder ejecta. The breech face isn't pushing back through a solid linkage to your hand. It's accelerating the combined mass of the barrel and slide assembly to the rear, resisted only by the recoil spring that's transmitting its compression force to the frame of the pistol that you're holding. During the time of the powder burning, the slide has moved to the rear only a small fraction of an inch, changing the spring's compression force very little. Most of the spring compression occurs as the slide moves back after unlocking and stopping the barrel, long after the bullet's left the muzzle, and what momentum's left after the spring's compressed is transferred directly to the frame as the slide hits the stop on the way back.

Heavier bullets will affect the timing of unlocking, which will occur earlier relative to the bullet's motion downrange. A 250 grain one's not much different from a 230 grain, though.

[StarMetal]

The longer pressure curve time still pushes different, for one thing it pushes longer.

Alot of folks don't realize that the hammer main spring in conjunction with the recoil spring work to control the slides rearward recoil, on the any hammer fired semi auto. It takes a small, but certain amount of energy to throw that hammer back. If you ever owned a Russian Tokarev you would know that. You can hardly cycle the slide without first cocking the hammer back. It's notoroius for that.

Joe

[Ricochet]

Yes, it pushes differently, but you can't feel it because it's pushing through a spring.

[robertbank]

By the time the recoil spring begins to compress the bullet is long gone and the recoil pulse is past. Travelling at 800 fps the bullet is gone, along with the recoil pulse in 1/72 thousandths of a second. What happens afterwards is the reaction to the thump you got.

Joe as soon as I can round up some of those bullets I am going to try Unique if I can find a load that first will make PF and still leave room in the case for the bullet.

I wish I had two things to play with a Ranson Rest, that I could afford but I can buy a Ruger .45 Colt for the same money and I want the Ruger! The 2nd would be some method of recording actual recoil transmitted. I know it can be calculated mathmatically but my days of doing the math required died when I left school (Like in 43 years in Banking I never once had to calculate the square root of a damn thing and I spent hours playing with that, combinations and permutations (once figured out the odds of winning the Loto) and a host of other formula that the world hinges on, in the eyes of my squirrely math teacher).

With apologies to my friend Felix who has a mind for physics and math.:-D

Take Care

Bob

[StarMetal]

Bob,

I have the 1911's and I have the Ruger Blackhawk old model with 4 5/8 in barrel, and I can tell you there is a major difference in recoil between those two guns. I know they are different, but the same loads have more kick out of the 1911's and it's not all because the 1911's have a sealed breach.

What I was trying to say that after the bullet is gone and the peak pressure too thump we're talking about is different from faster to slower powders. Be nice to have a machine that rated recoil and you could load a fast powder and a slow one, both to the same velocity and see what the recoil is.

Joe

[robertbank]

Joe

I agree and maybe I should write U of B.C. Engineering Dept. If a guy could get a University Prof interested in the subject it would be a heck of an exercise for the students.

Newton would tell you the actual recoil should be the same IF velocity, bullet weight and weight of the gun were a constant. Weight of powder required to achieve the former plays into the formula as well.

As an aside I wonder if the strength and size of the shooter
plays a part in perceived recoil.

Once I get the 500 bullets then I will be able to fix my loads with Bullseye (3.6 gr - Faster powder), and Unique (?Gr - Slower powder) to achieve roughly the same velocity. I am sure you are right but I would like to prove it for myself. I have a couple of guys I know who will be willing to be my subjects. I also will attempt a placeble test as well to see if what we expect to achieve or are told, affects our perceptions of what we achieve.

To be sure, it will be interesting winter exercise.

Take Care

Bob

[slughammer]

The 2nd would be some method of recording actual recoil transmitted.

Bob

Rob, a sophisticated measuring device can't predict the human factor of what load is better for what shooter. Just the same as some guys are using a lightened slide and some are running full dust covers, it's individual perception. The thing that is not individual perception is hit factor. Run a drill like El Presidente several times and record your times and points. Switch ammo and shoot till you get the timing down for the new ammo, then run the drill again a few more times with the second ammo. Again record your times and points. Time and points are what it’s all about.

For the faster vs. slower powder, you can run the same test. Perhaps Unique works better than Universal Clays at lower pressures, with UC I got lots of muzzle blast and extreme spreads pushing 100 fps.

[StarMetal]

Slughammer come up with an excellent idea. Run the tests like he said, see which you hit better with and see for yourself if the recoil impulses are different between fast and slow powder.

Joe

[robertbank]

Yes you are absolutely right . The machine would though, if set up right, either confirm or discredit certain "recoil" reducing methods. If say 100 rounds were fired over the test mechanism of several different powders all attempting the same velocity with the same bullet one could measure the recoil, timing etc of loads that achieved exactly the same veloitcity. You could measure time of recoil, length and a number of likely meaningless real world stats but, hey, Universities have been known to study lots of meaningless things in the search for knowledge.:mrgreen:

Times and Points are indeed what it is all about, I shoot 9MM in IDPA and IPSC Production. I have reduced recoil via reduced charges to as low as I dare go and still stay with PF so now it is all about practice, practice and more practice which is likely all that matters anyway.

I found 4 gr of Unique under my cast 125 gr bullets provided the lowest extreme spreads and SD's with single digit SD's recorded in all my 9MM guns. I have achieved the same thing using Win 231.

In my guns the sweet spot seems to be:

Unique 1025 to 1050 fps
Win 231 1125 to 1130 fps

using Lyman's 355402 bullet sized to .357 COL 1.115


Take Care

Bob

[robertbank]

HI Joe, I'll do that with my .45acp. Just switched press to 9MM but will load .45acp tomorrow. I'll get some bullseye loads and try my best to match them to Unique as far as anticipated veloicites are concerned. In order to be a true test I'll have to try to keep velocity as a constant. Oviously, the bullet will be the same.

Take Care

Bob

[StarMetal]

Yes, it pushes differently, but you can't feel it because it's pushing through a spring.

John, I don't believe you are totally right. In a 1911 the barrel and slide stay locked together until the link cams the barrel down out of the locked breeck position, barrel stops any rearward movement, and the slide, of course, continues on from momentum. We'll take a look at that momentum in a second or two here, first let me say that went the barrel unlocks, that bullet is gone or it better be!! Second let me say the distance that the slide and barrel travel back together still locked in a 1911 is about, I say about, 1/8 of an inch. From beginning of that 1/8 inch to some point to where the bullet exits, the recoil is almost totally on a locked up solid platform. I doubt for one second that the spring pressure makes much difference in that short span of time. Concider too that the hammer has struck the firing pin and is laying against the rear of the slide. So recoil is pushing against the weight of the whole pistol until it overcomes the force needed to more the slide rearward and overcome starting the hammer to recock. Okay, now back to momentum. After the bullet has exited (before the barrel unlocks) and the barrel cams down and the slide continues back soley from momentum of eneryy instilled in the slide. There is a big difference in a totally blowback nonlocked breech system in a 45 acp in felt recoil then in a 1911, or any other locked breech system. You ask who makes such a total blowback 45acp? I'll name two, the current semi-auto Thompson submachinegun and HK's UPC legal subgun. Both of these rely on a massive bolt block, and believe me, not recoil spring. You could hardly call small light dutyrecoil springs in those two firearms much of a recoil spring. They merely force the bolt back forward. You'll say well the semi Thompson is quite heavy. Yes true, but the HK subgun isn't John, it's totally plastic, including the receiver, and the hammer/trigger mechanism. The only steel parts on it are the barrel and the bolt. So it's light, not much recoil at all, not even more then the much heavier Thompson. At any rate a locked breech at the moment of firing is pretty much a solid lockup.

Joe

[Ricochet]

Joe, you're analyzing the situation incorrectly. Of course the slide and barrel are locked together solidly for the time the powder is accelerating the bullet down the bore. That locked unit is not directly connected to the frame you're holding in your hand. It's free floating. The rearward pressure is transmitted to the frame through the recoil spring, and as you pointed out, also through the mainspring. What you're feeling during that time is the same pressure that's transmitted when you pull the slide back by hand to cock it, whether it's a high pressure or low pressure load, a fast burning powder or a slow one.

If someone wants to rig up a device to prove or disprove what I'm saying, it'll need a pressure transducer behind the frame that displays the pressure/time curve of the entire recoil event, from firing till the slide stops at the rear. Same idea as the displays with chamber pressure measurements with the piezo transducers. The time of interest is while the bullet's still in the bore. I predict that part of the curve will be practically indistinguishable with all loads.

[robertbank]

The time frame, assuming the bullet is travelling 800 fps is about 1/72 thousanths of a second from start of ignition until the bullet leaves the barrel. During that time the barrel does rise before thr bullet exits but it is, this time that felt recoil, perceived recoil and actual recoil all takes place. It can't take longer becasuse no addtional energy is added once the bullet exits the barrel. In fact maximum recoil would take place at the moment the bullet begins to move and must decline afterwards as the bullet moves down the barrel. I guess the only question I have is, "Does the pressure build differently and significantly enough to be noticeable within the time frame we are talking? Some say it does.

Before we go off and ask an engineering department for help why not run a blind test. Load 40 rounds using Bullseye and Unique, using the same bullet and as close to the same velocity. For test purposes, say 750 fps for both powders. It will be necessary to chrono loads until we have essentially equal cartridges firing the same bullet at the same speed. Once this is accomplished two expereinced shooters should be given a blind test with each shot recorded. To add to the test we should have one round completed dis-similar either loaded way lighter or way heavier.

The first tester should be told he is shooting loads of equal power and he is to determine which provides the most recoil and to describe it, sharp, push, shove etc.

The 2nd tester be told he is shooting two loads one of which is much heavier than the other and he is to determine which load recoils the most.

After the test we can exaim the results. I added the 2nd test because often what we perceive is what we expect to perceive or what we have been told to perceive.

I have no idea of the results but for the heck of it I am going to do the test over the next couple of weeks. I think I have enough data stored to find loads for each powder of capable of driving a 200 gr lswc at approximately the same velocity. Results will be very subjective but we will see if there is a pattern.

Take Care

Bob

[StarMetal]

Firing Phase A: Lugs horizontally engaged

Firing is split into two phases because of the thrust vector existing between the bullet and the breechface, which horizontally engages the locking lug surfaces while the bullet is under pressure in the barrel. Firing occurs in the M-1911 pistols when the grip safety is depressed; the trigger is squeezed; and the interaction of the trigger, disconnector and sear releases the hammer. The released hammer then transfers its energey to the inertial firing pin, which, in turn, strikes the primer. As the primer ignites the propellant charge in the chambered cartridge, the hot powder gasses expand, building pressure that forces the bullet down the barrel. As shown, the barrel and slide remain locked together both horizontally and vertically during the initial firing phase.

http://www.m1911.org/operation/m1911-05.jpg
Firing Phase B: Horizontal disengagement

At the end of the firing phase, the bullet exits the muzzle and drops gas pressure inside the barrel. Bullet departure breaks the balanced thrust vector established when the bullet was in the barrel as in fig. 4A. In terms of the effect on the pistol, this action enables the top locking lugs to horizontally disengage (see National Match barrel note in next phase) and imparts a rearward force on the slide assembly equal to the inertia of the departing bullet. Then, because the slide assembly has a greater relative rest mass -plus the added benefit of the recoil spring- inertial energy is absorbed as the slide recoils to the rear.

http://www.m1911.org/operation/m1911-06.jpg
Unlock/Linkdown Phase: Vertical locking lug disengagement

In pistols with standard ordnance dimension barrels, barrel linkdown and vertical locking lug disengagement begin momentarily after the lugs horizontally disengage at zero breech pressure just after the firing of a chambered round. Fired cartridge case extraction (see next phase) actually begins at the start of barrel linkdown with the initial breaking of friction between the fired/expanded cartridge case and chamber wall, as show at A below. Note: National Match barrel hoods are hand-fit to maintain horizontal lug engagement until the barrel links down.


Notice that the slide and barrel didn't move that 1/8 inch till after the bullet was looooonng gone. So what I'm talking about it what is it you feel in your hand the micro second after the firing pin strikes the primer. The slide and barrel aren't moving, the bullet has gone down the barrel. Also the pressure you feel isn't such as you said basically the same as pulling the slide back by hand. You feel recoil immediately when the bullet fires. If the slide is that free floating then why is your hand starting upward upon ignition of the powder? And that's before the slide ever begins to think of moving. One more shot: Racking the slide back and functioning it by hand are entirely different then powder gases and bullet functioning it.



What needs to be build is a special 1911 that you can lock the slide and disable the automatic cycling and feeding and compare the recoil felt from that to when it isn't disabled.


Joe

[robertbank]

"What needs to be build is a special 1911 that you can lock the slide and disable the automatic cycling and feeding and compare the recoil felt from that to when it isn't disabled."

Joe that really isn't necessary as the amount of recoil can be calculated exactly by mathmatics and indeed has been done. What we are really dealing with here is perception and perceived recoil and whether different powders producing the same velocities with a given bullet can and do provide different discernable differences in recoil. Newton's Law would suggest if the bullet exits the barrel taveling at a fixed speed out of a 5" barrel the amount of energy going backwards should be the same as what caused the bullet to go forward. I think you are saying that different powders provide that energy in different time frames hence the difference in felt recoil.

Man I am way of of my field and the posts probably show it BUT I wil learn.

I can't argue this business about the slide but I am told by very gifted folks in this area that the slide moves approx 1/10th of an inch before it unlocks. 1/8th or 1/10 be that as it may I am told it does move. I think I am saying or someone is that the the above illustration is in error. I am not because I don't know.

Take Care

Bob

[StarMetal]

Bob,

I think you're doing fine.

Yes the slide travels about that amount before it unlocks. What I was saying too, it the bullet is long gone, long long long gone before the slide even moves. The barrel cannot unlock either until the horizontal pressure on the locking lugs is released and that doesn't happen until the bullet leaves the barrel then the pressure is gone. There is a time period where the slide does nothing for some microfractions of a second. It's almost like the slide then recoiling back is a delayed action. I believe the real name for the 1911 action (and a whole host of others similar to it) is a delayed blowback action. The lug lockup is what delays it from being totally a blowback design.

Here's something for you to try with an empty gun. Please make sure it's empty, you don't even need to have the magazine in it for this. Grasp the muzzle of the slide by the sides with your thumb and index finger firmly with one hand while holding the grip in the other. No finger needed on the trigger. The push the slide back fast and hard. It will go all the way back. Do this with the hammer cock as that will make the test easier. Okay return the slide to full battery and this time, with hammer back again, put your thumb on the barrel muzzle, making sure that it's not in the way of the recoil spring guide rod if you have one installed on the pistol. You want to make sure you're just pushing the barrel, not the slide in any way. Now notice it goes back about that 1/8 or 1/10 inch and is solid and won't move any further. This kind of explains the horizontal locking pressure of the locking lugs on the barrel and slide. Remember I said the barrel won't link down as long as that is present? This is why I say you feel some real recoil. I believe this is why John and I are disagreeing.

Joe

[robertbank]

Well step one in the learning curve is there. Did it and it does! Canucks are kind of thick headed you know. :mrgreen:

Now here is a point to ponder. I say the entire recoil of the gun takes place within the time frame of the bullet exiting the barrel. What we see afterwards is a reaction to that recoil ie the barrel rising in the hand and twisting. That isn't recoil that is a reaction to the thump you got from the recoil. I suspect strong armed men/women would control recoil better than weaker persons but the recoil, all things being equal is the same whether you are strong as an ox or not.

This brings me back to my test which I will conduct before October is out.

Take Care

Bob

ps Newton also says the heavier the gun the less felt recoil. To your post #21 your Rugers are heavier than the 1911 n'est pas. Thought I would throw in the sum of my French. Canada is bilingual you know. LOL

[StarMetal]

Another line of thought here that is wrong is that if you acheive the exact same velocity with a the same bullet, but using different powders that the recoil is exactly same. Now this is more noticeable in rifles so let me explain. I you take a 300 Win mag with a 180 gr bullet and push it to a certain level of velocity, then duplicate that velocity with a large column of really slow powder, the one with the larger column of slower burning powder will have more MEASUREABLE recoil. The factors that determine the recoil of a certain load are the weight of the bullet, the weight of the rifle, the velocity of the bullet, and the weight of the powder column. Like I said, the weight of the powder column in a pistol round is very small, but if the machinery is super sensitive, it would be able to measure it, and it would be different then the same velocity load, with said same bullet, but with faster lighter powder.

Joe

[robertbank]

Joe I agree there will be a difference due to the weight of the powder however, in pistol we are talking the difference say between 4.6 gr of bullseye and 5.2 Gr of 231. 6/10ths of a grain is not going to have a measurable effect on recoil that is detectable by humans I don't think. To be fair the amount of ejected gases also is part of the equation and maybe even be more significant than the weight of the powder. How significant in the total amount of recoil generated can be left to the mathmeticians here. I'm still stuck doing combinations and permutations and finding the sqare roots of numbers.:-D
Leave me to my test and I will report back the outcome. I don't recall this kind of work in all the life insurance ads on retirement! Where is the sand, blue water, sun and half clad females?:???:

Take Care

Bob

[Ricochet]

Notice that the slide and barrel didn't move that 1/8 inch till after the bullet was looooonng gone. So what I'm talking about it what is it you feel in your hand the micro second after the firing pin strikes the primer. The slide and barrel aren't moving, the bullet has gone down the barrel. Also the pressure you feel isn't such as you said basically the same as pulling the slide back by hand. You feel recoil immediately when the bullet fires. If the slide is that free floating then why is your hand starting upward upon ignition of the powder? And that's before the slide ever begins to think of moving. One more shot: Racking the slide back and functioning it by hand are entirely different then powder gases and bullet functioning it.


That all sounds very impressive, Joe, but contains no truth.

The slide and barrel indeed are moving as the bullet is moving. "For every action, there is an equal and opposite reaction." The momentum imparted to the bullet (and powder charge) during the acceleration of the bullet from breech to muzzle is the same as that imparted to the recoiling part, which is the barrel/frame unit. The rearward movement of the slide and barrel will be proportional to the movement of the bullet, the ratio being determined by the masses of the combined slide/barrel unit and of the bullet (plus about 1/2 of the powder weight, which is negligible in the .45 ACP.) The ONLY force transmitted from the slide to the frame is that transmitted through the springs, and the (negligible in a gun in good condition) force of sliding friction. The force IS exactly the same as that transmitted when you pull the slide back by hand. It's a simple mechanical system. You're imagining that the slide is somehow immovably locked to the FRAME until the bullet has left the barrel. That's not the case. The slide is locked to the BARREL, they both move freely together through that short distance until the link pulls the barrel down and unlocks it. Then the barrel is stopped, and its momentum is transferred to the frame. The slide's momentum is transferred to the frame as it continues compressing the recoil spring, pushing back the hammer and cocking it, and finally when it hits the stop with its remaining momentum that the spring hasn't absorbed.

Julian Hatcher wrote a whole chapter on gun movement while the bullet is still in the barrel in his Notebook, which is recommended reading. It explains what I'm saying in greater detail than I have time or energy to type. No need to reinvent the wheel, anyway, this stuff's been known since Newton's time.

As for a special M1911 with the frame locked to the slide, that's been done. It does greatly reduce the recoil. The relatively light slide moving freely builds up more recoil energy than the full mass of the gun (and the hand holding it) would. Just like a Browning recoil operated shotgun will kick you far more than a fixed-breech shotgun of the same weight. Or like any long gun will kick you harder if you hold it out in front of your shoulder instead of firmly against it.

[felix]

Don't forget in your discussions: component accelleration, which actually makes up the derived forces. Velocity has no effect on what we actually feel, so keep that in mind. ... felix

[StarMetal]

John,

You're theories sound impressive too, none the less still wrong. You messed up here too pal, you said: The slide is locked to the BARREL, they both move freely together through that short distance until the link pulls the barrel down and unlocks it. I say: The slide makes no vertical up and down movement (just what slack there is in the slide to frame rails). The slide only moves horizonally. It is the barrel that this LOCKED to the SLIDE. The difference is the slide can still do it's horizontal movements, the barrels movements during the locking phase are stopped, except for it having to follow the slide horizonally rearward for a very short distance. You are wrong in stating I think the slide and frame are locked together during firing. I do believe the bullet is gone from the barrel before any appreciable movement of the slide can be measured. The energy that the combustion of the powder transferred is absorbed by the, well, the whole pistol, so that means the slide, barrel, and the springs. being these things can move, the stored energy vents by moving them.

Yes I know locked slide 45acp's have been invented. I'm very familiar with silenced weapons in the World Wars and other wars. In fact I've seen locked slide P38 Walthers. I know that there is noise made by slides functioning and casings being extracted and falling on the floor or ground. How can a locked slide 45acp have less recoil? You yourself believe in all the scientific theories like the one for every action there is an equal reaction? I think what you are looking for is there is a different "perseived recoil". One cannot not get rid of recoil (energy) he can only slow it down so it perseivabably feels like it's less.

Joe

[robertbank]

Lets keep it cool guys. Newton's Law is a Law not a theory. In Hatchers book he describes the rising of the barrel that occurs prior to the bullet leaving the gun Joe. It is not large obviously but it does occur.

Quoting Hatcher page 301 of "Textbook of Pistols and Revolvers"..."the pressure of a ton or more on theinside of of the breech of the gun, tending to push the the gun suddenly backwards, operates in a line that lies above the center of gravity of the gun, and therefore tends to rotate the gun around a horizontal axis through the center of gravity of the gun so that the barrel moves upward. Thus the bullet, while it is moving forward is moving through the barrel that at the same time is rising. This motion is equivalent to giving an upward flip in addition to its forward motion. Thus the bullet will strike a point on teh target that is above the point toward which the barrel was pointed when the trigger was pulled."

Hatcher provides a table indicating a powder charge of 4.6 gr under a 230 gr. bullet travelling at 810 fps out of a 5" gun weighing 39 oz. will generate 4.5 ft lbs of recoil energy.

I have no idea what any of this adds to my test but it is interesting to know...I guess.

Take Care

Bob

[StarMetal]

Bob,

I didn't mean theory in that respect, I meant Law.

Ok you said: This motion is equivalent to giving an upward flip in addition to its forward motion. Well I wasn't going to mention that in the last post, thought it might be too deep for John, but now that you have, doesn't that kinda make the slide, the barrel, ah well, the gun kind of solid for some microsecond? I was reading about the new new Benelli recoil operated 20 ga Lighting shotgun and there's a part in the bolt assembly, that upon firing and recoil actually pushes forward on the bolt, this in fact keeps the bolt lugs locked tighter until the pressure drops in the barrel. There's alot more going on in a 1911 then just comparing it with pulling the slide back by hand.

Joe

[robertbank]

Yes it does. The recoil energy is over with at the instant the bullet leaves the barrel and for all reasons stated no parts of the gun move until the bullet is gone.

In Hatcher's book in the same chapter he mentions the effects of powder charges on recoil and while it has a large effect on pistols loaded with black powder, with smokeless powders the effects in pistols is negligible given the relatively small charges involved.

Take Care

Bob

[StarMetal]

John,

I"m :kidding: pardner. You're alot of fun. Personally I think you're a pretty intelligent man and in so many diversified fields. I'd like to talk to you sometime and discuss your educational background. When I first met you I thought you were just a General Practitioner Doctor, boy I was wrong.

You mentioned that you were just a hop and skip from Widners, well I'm a hop and skip from them too. I have a place to shoot on my property and you should drop by some day for a shooting extravaganza.

Joe

[Ricochet]

Well, likewise, Joe, I know you're a smart, experienced and interesting guy, too, and I both like and respect you. You're just dead wrong in this case and not seeing it. That's OK. You're entitled to your incorrect opinion.

It's not possible for the slide and barrel to not move while the bullet is in the bore and start moving after it's gone. All the motion has been imparted during that time.

And there's still no direct connection between them and the frame.

The laws of physics don't change for things that happen fast. Not till you get pretty close to the speed of light, anyway, and that 1911's not in that league.

[StarMetal]

Good enough John [smilie=1: but I've seen high speed photo's of 1911's firing and there's the bullet just out of the barrel and doesn't appear the slide moved yet.

Joe

[Ricochet]

Well, if one of us goes to the trouble of getting out his 1911, breaking it down and carefully weighing the slide-barrel combination, we can come up with a pretty good estimate of how much (little) it moves while the bullet's in the bore. Multiply the weight in pounds by 7000 to put it in grains. Divide 230 (for standard hardball) or 250 (for this cowboy boolit) by the result. Multiply that by about 4.5" for the bullet travel from its starting point in the case to muzzle exit and you've got how far in inches the slide would have recoiled back while the bullet was going down the bore. Neglecting the movement of the small powder charge in the bore, the mass of the hammer, and the force to compress both the recoil spring and mainspring through the very short distance calculated.