im not a rifle guy. I usually shoot shotguns, ml, handguns and shoot to sight in and done until next year so im a little ignorant to some things.
Chronograph Question
- Thread starter Axis II
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The indentations of the firing pin can look different due to the shape of the new firing pin's nose, if the radius is more rounded than the old one it will probably create the impression that it is penetrating deeper - and it might be but it would probably be so slight that it wont be problem.
Bingo - I suspected that you were using Hornady V-Max bullets, everybody seems to think that Hornady's reloading manual shows light loads but the reality is that Hornady bullets are shaped different than most other brands (longer shanks) and the result is that they produce higher pressures due to more of the bullet being seated in to the case.
In addition to the V-Max creating more pressure, you are using a slightly shorter COAL than Hornady recommends for the 55gr V-Max (they recommend 2.250") so you are using a bullet that has a longer shank than most other 55gr bullets and you are seating them deeper in the case than recommended - added together that results in higher than expected pressures.
Hornady recommends;
Trim-to-Length of 1.750"
Cartridge Overall Length of 2.250"
H335 Powder Charge of 20.8 to 23.2 grains
Using their recommendations in a 26" barrel and using Winchester brass they get muzzle velocities of approx. 2800 to 3100 feet per second. Those velocities would be produced by max pressures of around 31000 to 43000 PSI, 24gr would produce max pressures of around 50000 PSI with a muzzle velocity of around 3200 fps using the same barrel length and cartridge case. The SAAMI max pressure is 55000 PSI so the load wouldn't blow up the rifle but in a gas gun it's getting pretty hot.
I'd recommend getting a chronograph and verifying the muzzle velocity, try not to exceed Hornady's recommended 3100 fps (that will actually be less if your barrel is less than 26"). Increase the COAL to Hornady's recommended length, 2.250", and then reducing the powder charge weight a little. If you are using a gas gun you also have to worry about the pressure at the gas port, not just the max chamber pressure.
In addition to the V-Max creating more pressure, you are using a slightly shorter COAL than Hornady recommends for the 55gr V-Max (they recommend 2.250") so you are using a bullet that has a longer shank than most other 55gr bullets and you are seating them deeper in the case than recommended - added together that results in higher than expected pressures.
Hornady recommends;
Trim-to-Length of 1.750"
Cartridge Overall Length of 2.250"
H335 Powder Charge of 20.8 to 23.2 grains
Using their recommendations in a 26" barrel and using Winchester brass they get muzzle velocities of approx. 2800 to 3100 feet per second. Those velocities would be produced by max pressures of around 31000 to 43000 PSI, 24gr would produce max pressures of around 50000 PSI with a muzzle velocity of around 3200 fps using the same barrel length and cartridge case. The SAAMI max pressure is 55000 PSI so the load wouldn't blow up the rifle but in a gas gun it's getting pretty hot.
I'd recommend getting a chronograph and verifying the muzzle velocity, try not to exceed Hornady's recommended 3100 fps (that will actually be less if your barrel is less than 26"). Increase the COAL to Hornady's recommended length, 2.250", and then reducing the powder charge weight a little. If you are using a gas gun you also have to worry about the pressure at the gas port, not just the max chamber pressure.
Reloadron
Contributing Member
Yeah, that does seem to happen. Enter the new to reloading shooter. I figure every reloading enthusiast starts somewhere. Many of us began the venture long before there was an internet and gun related forums to get dope from and exchange ideas. Even today the new reloader is faced with a pile of terms and no shortage of acronyms. Getting the terms correct is a challenge and takes some time with a few mistakes along the way. ohihunter2014 is very quick to admit he is quite new to much of this and seems to run with a bit of fear. Once you have seen enough blown up rifles you get a little nervous. I have exchanged several PMs with him and he is very sincere and tries to get things right. He is trying to work his way through the learning curve, including the terminology.
Then we have things like scorching hot. What exactly is scorching hot? I see it as where we blister skin upon the touch. Another classic is I want to get a long range rifle, what should I get? My long range is when we get out beyond around 600 yards? However, many when asked come back with shooting a deer at 200 yards?
Learning to look at a flattened primer is another good example. Half the flattened primers I see posted look fine to me.
So yeah, I agree that in some of the cases the OP is interpreting things incorrectly but I figure that runs with the learning curve. On the bright side he ask plenty of questions.
Ron
I grew up in Arizona and I can tell you quite honestly that if the ambient temperature is already in the 90's or above then it wont take long to push the barrel up in temperature, especially if you're talking about a pencil profile .223 barrel. I've actually done temperature testing on my Springfield SOCOM with a 16.25" barrel in .308 Win and I know that you can push the temperatures above the comfort zone (over 130 degrees F) pretty quickly. To a new shooter I'm sure that the problem is that they have no relative frame of reference, they've never felt a hot barrel before so they don't know what's normal.
factory v max is around 2.230-2.235. if I go higher than 2.235 I cant close the bolt without being forceful and jamming the bullet into the rifling. I hate spending money on stuff that just sits there or something I will only use 1-2 times and done that's why I wanted to know 110% should I be concerned with what I am seeing and should I get a chrony.
I have about 300 rounds of 223 under my belt and I have found 2 loads that shoot either 5 in a hole I can stick my finger in or close to it. my main goal is to save money on ammo for hunting, target and make waaay better ammo than factory but I also cant afford a new rifle because I'm shooting 4k fps rounds and burning the barrel up. I found 2.235ish to be the spot where i can close the bolt without beating is closed with a hammer and measured factory v max and figured good for factory good for me. all of them chamber great, shoot great, but i was concerned about the heat. i have gotten AR-15 so hot it would give 2nd degree burns but this a bull barrel bolt gun i have. last night i shot and was pressed for time cause i had my handicap uncle with me and it went a little longer than expected so i shot 5 and changed a target and shot 5 more hand feeding them and the first 3 hit the same hole and 4-5 were about an inch apart and i couldn't touch the barrel. Im kinda over my fears cause nothings happened yet and they shoot great.
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I just re-read your earlier post about not being able to increase the COAL, if that's true then I'd recommend reducing the powder charge weight a little, but the only way you can get some idea about the chamber pressure without buying a pressure transducer is if you buy a chronograph. Then adjust your powder charge to balance accuracy against max recommended velocity. You may be able to push those loads hotter than Hornady's recommended speed but if you do then you have to worry about throat erosion and, as I mentioned before, proper gas port pressure if you are using an AR.
I do wonder how you've discovered the max COAL, what process did you use? I only ask because it's hard to believe that the lands would be too close to use a standard COAL. If that's true then I'd suspect that there is a problem with the chamber or the barrel being set back too far. Is the rifle an AR?
I do wonder how you've discovered the max COAL, what process did you use? I only ask because it's hard to believe that the lands would be too close to use a standard COAL. If that's true then I'd suspect that there is a problem with the chamber or the barrel being set back too far. Is the rifle an AR?
When you tested the overall length (by loading a cartridge in to the chamber) did you remove the bolt guts? If you leave the firing pin, ejector, extractor in then they can prevent the cartridge from seating against the bolt face when you try to chamber the cartridge. In effect the cartridge will be pushed forward and the bullet will contact the lands before it should - you will see a shorter COAL than you actually have.
its a savage axis 2 bull barrel. I shot maybe 50 factory rounds through it and didn't shoot it for a year and even those the bolt was a little hard to close. i started reloading v max at 2.250 and the bolt was hard to close and would leave a bright sharp cut in the ogive of the bullet and when needed i couldn't open the bolt because it was jammed into the rifling. i then measured a factory v max at 2.235 and made a dummy round and colored it with a marker and chambered it at 2.250 and the bolt was hard to close and left marks on the bullet by the ogive. i would seat from say 2.250 to 2.245 and do the same thing and still get marks until i hit about 2.235-2.237 area the marks started disappearing and I could chamber and unchamber the rounds without hesitation.
With h335 23.6-24.6 shot the best but the higher I went the tighter they got. i was thinking to save the $70 i will see if someone at my club had a chrony and might take the time to shoot with me so i don't have to spend the extra money. i got slammed with a couple hospital bills, student loan issues, and not lack of work so trying to put that money towards finishing the 9mm i started and 44mag before hunting season.
With h335 23.6-24.6 shot the best but the higher I went the tighter they got. i was thinking to save the $70 i will see if someone at my club had a chrony and might take the time to shoot with me so i don't have to spend the extra money. i got slammed with a couple hospital bills, student loan issues, and not lack of work so trying to put that money towards finishing the 9mm i started and 44mag before hunting season.
OK, it's a Savage but did you disassemble the bolt when you tested for COAL? The extractor is pretty heavy on that bolt and it will definitely push the cartridge forward. As an alternative you could also try snapping the cartridge in to the bolt face and under the extractor before you push the cartridge forward. You will have to remove the bolt from the rifle, insert the cartridge under the extractor, and then insert the bolt with the cartridge in the rifle and chamber it.
I had to send it in to savage for the bolt locking up even on an empty chamber and asked about the throat being short and the extractor/ejector dropping rounds into the chamber without ejecting them and everything was replaced. i don't know jack squat about the bolt. i will say before i sent it in i couldn't even get to 2.235 and even factory v max would be hard to chamber but not being into reloading at that point i ran with it and slammed the bolt home and shot and hunted with it. measured that batch and they were 2.233 was the longest and short being 2.230. i think i can max out around 2.237 or so. i cant remember off hand.
spitballer
Member
...indeed. Consider a five-shot group from this morning with a Rem 700 .223 at 200 yds with 55gr Nosler BT bullets, H4895, Nosler cases, and CCI #400 primers. Velocity as follows:
3316
3383
3375
3361
3370
Okay, big deal - typical velocities for a max load, right? Wrong. These velocities were achieved using just 24.53 grains, less than the published minimum. Admittedly a 30" barrel boosted velocity to some degree in this instance, but the point is that without a chronograph to get one's bearing it's easy to overdo it with a long gun. The max published 55gr velocity for any propellant that I've seen is Varget, which tops out at 3384 if I remember correctly, and my suspicion is that it's asking for trouble to try to push 55 grain pills faster than that with any propellant, barrel length notwithstanding. If you care about your equipment and your safety a chrony is a very worthwhile investment IMHO, even if it's a cheap one.
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Nature Boy
Member
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The chrono tells you info about your loading process you can't get otherwise. For $100, why not have one
RPegram
Member
I bought a chronograph last fall. I used it with my 223 loads and have not used it for any pistol rounds. After using, I relied more on accuracy of the loads than any data gained from the chrono. I only gained knowledge of velocity of my favorite loads. It is fun to play with. I have thought about selling, but I decided it would be nice to have around if I decide to develop a load with velocities close to some of the advertised velocities of self defense loads.
For a hot barrel, try 30 rounds of 223 through an AR in sixty seconds and you can get rid of all gun lube on the barrel in a hurry. I bought one of those self healing, orange cubes from Wally World, tie it on a board with about 6' of string and see how fast I can make it spin. I get to shoot at a private range, so I get to play a little.
For a hot barrel, try 30 rounds of 223 through an AR in sixty seconds and you can get rid of all gun lube on the barrel in a hurry. I bought one of those self healing, orange cubes from Wally World, tie it on a board with about 6' of string and see how fast I can make it spin. I get to shoot at a private range, so I get to play a little.
ArchAngelCD
Member.
I have a Howa 1500 rifle made before they started using a Hogue overmolded stock so I have a cheap plastic stock too.
When I load a 55gr Sierra FMJ bullet #1355 I load it to 2.235". When I load a 55gr Sierra BTHP #1390 I load it to 2.255". It seems you have an extremely tight and short chamber so you will need to load what it wants. That's not good or bad, it just is...
BTW, the #1390 round us loaded with 25gr Varget and it's a sub 1/2MOA load all day long out to 250 yards. The other 55gr loads are all made with 25gr H335.
When I load a 55gr Sierra FMJ bullet #1355 I load it to 2.235". When I load a 55gr Sierra BTHP #1390 I load it to 2.255". It seems you have an extremely tight and short chamber so you will need to load what it wants. That's not good or bad, it just is...
BTW, the #1390 round us loaded with 25gr Varget and it's a sub 1/2MOA load all day long out to 250 yards. The other 55gr loads are all made with 25gr H335.
tcoz
Member
If it's a black barrel and sits in the sun for 15 minutes or so with 90 degree temps, it'll probably be very hot to the touch without putting any rounds through it.
Don't you have reloading manuals? You should have several which tell you all about the power of loads with different weight bullets shooting different weights of many powders and various primers. More powder means more power and hotter barrel.
No you do not need a chronograph. You might enjoy having one and learn things through using one. They do not replace reloading manuals though.
No you do not need a chronograph. You might enjoy having one and learn things through using one. They do not replace reloading manuals though.
I agree but without the chronograph you have absolutely no idea if the powder charge you used matches the reloading manual's predicted velocities. If your load pushed the speed higher than the manual predicted then you obviously have higher pressures than the manual's authors expected, and if the speed is high enough then you know that you have a dangerous issue.
I just don't understand why people think that a chronograph is a toy, it's an important tool that helps you verify that the load is doing what you think it should be doing. Without it you have no idea about what is happening inside your firearm.
mmorris
Member
We also don't need torque wrenches, thermometers or speedometers, but they make for a more controlled or predictable outcome.
All my reloads make lots of noise, put bullets in the target and push the gun around in my hand. My brain-and-meat system cannot reliably tell the differences or similarities between shots to my satisfaction. I like to have as many unquestionable measurements as I can get when the thing I really want to know (pressure) is not measurable (by me).
We repeatedly see this type of statement in threads about load development:
When you consider that we don't have published data on, and don't routinely measure, case volume w/bullet, this seems like a good argument for using a chronograph, Max Load or not.
Maybe we don't have to own one, but I think we should consider the data important enough to borrow or rent a unit to test the loads we develop. Once a load is proven, I agree there is little need for additional chrono data.
That is, until you change powder or primers or bullets.
All my reloads make lots of noise, put bullets in the target and push the gun around in my hand. My brain-and-meat system cannot reliably tell the differences or similarities between shots to my satisfaction. I like to have as many unquestionable measurements as I can get when the thing I really want to know (pressure) is not measurable (by me).
We repeatedly see this type of statement in threads about load development:
When you consider that we don't have published data on, and don't routinely measure, case volume w/bullet, this seems like a good argument for using a chronograph, Max Load or not.
Maybe we don't have to own one, but I think we should consider the data important enough to borrow or rent a unit to test the loads we develop. Once a load is proven, I agree there is little need for additional chrono data.
That is, until you change powder or primers or bullets.
ljnowell
Member
I cannot agree with that. You simply find out what that load does in your gun vs their gun or test barrel. Unless you are using the EXACT same gun they did it doesn't necessarily mean that at all.
mmorris
Member
My point
That's the point, you want to know what your rifle is doing compared to their predictions.
If your rifle has the same barrel length and you get anything over 100 fps faster then you better start looking at what's going on; you might have hotter temperatures, shorter COAL, way too long COAL, smaller case capacity, or some other differences. But there is a reason and rather than just blindly going on, you need to know what's going on.
Regardless of the differences between the equipment, if you find that you are getting higher speeds than they got then you need to know why. Just saying that it's the way the load performs in your rifle isn't good enough, you need to know why it's producing higher speeds and how much. There is a reason for those higher speeds and while it could be because of perfectly safe issues it could also be because of mistakes you made in the loading process or mistakes you made in selecting components for the cartridge. Use some common sense, if your barrel is longer than the barrel they used to develop the load then you should expect that you will get higher speeds, but if your barrel is only a couple of inches longer and you are getting a speed increase of 500 fps then you'd better be looking for other issues. Maybe the powder charge is just high enough to still be safe but it might be pushing the bullet so fast that you burn out the throat in a few hundred rounds, with the chronograph you would know, without it you would have no idea until your gunsmith told you that you needed a new barrel. I've got a really nice 110gr Vmax load that I fire from a M1A SOCOM, it groups MOA or better, but without my chronograph I wouldn't have known that I was pushing those bullets at 3200 fps which is so fast that my barrel would have the throat eroded in a few hundred rounds.
mmorris
Member
I agree completely with macgrumpy's post.
I must say that I do not like to see highly experienced reloaders advise completely inexperienced reloaders not to use tools that can confirm their safe progress to proficiency.
If a new reloader doesn't know the basics that well, how can they be certain that the rounds they assemble are performing safely?
I must say that I do not like to see highly experienced reloaders advise completely inexperienced reloaders not to use tools that can confirm their safe progress to proficiency.
If a new reloader doesn't know the basics that well, how can they be certain that the rounds they assemble are performing safely?
mmorris
Member
If money is an issue, get a friend to shoot your firearm over their chrono, rent one, or buy and resell later.
Unhappiness is sure to result if the only measure of satisfaction is how little money and time ammo production requires.
Unhappiness is sure to result if the only measure of satisfaction is how little money and time ammo production requires.
ljnowell
Member
Many of us experienced reloaders learned a long time ago that staying within published data and looking for best accuracy works great.
I couldn't care less how fast my loads are going, they are within published data and I'm concerned with groupings. SD and ES don't concern me either, groupings do.
Chrono's are nice, but hardly required or needed.
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