.223 problem.


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longrifleman
January 6, 2013, 09:36 PM
I'm trying to work up a load to use to put away some ammo for just in case. I wanted it to be close to mil surplus. Published velocities aren't far from what various manuals list, and I wasn't going to be real particular, just consistent across a lot of rounds.

I wanted 2800 - 3000 fps with 62 gr pulled bullets and all my manuals said it shouldn't be a problem.

I checked the set-up of my chronograph with some Wolf plinking stuff and got avg velocity of 2928 fps - so far so good. I shot a string of W748 @ 25.5 gr; max load and got 2219 fps. Manuals said 2900 +/- fps. Tried the same weight again in case I screwed up and got the same results. I also tried a string with 26.4 gr which was the max load from an older manual but above max for the newer ones. Avg. velocity of 2284 fps.

I switched to Accurate 2520 @ 26gr -max load and got 2171 fps. Manuals predicted 3000 fps +/-.

I finished of the box of Wolf crap and got 2882 fps.

Rifle is a Stag 20" heavy barrel. Winchester primers. Bullets were crimped.

If the Wolf wasn't getting acceptable velocity I would suspect the chronograph, but it seems to work fine. With other calibers the results are reasonably close to the manuals.

What am I doing wrong?

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nastynatesfish
January 6, 2013, 09:42 PM
Use varget or H4895. I also use TAC

mtrmn
January 6, 2013, 10:05 PM
Make sure the chrono is at least 10 feet away from the muzzle. Gases from the muzzle blast will screw with your readings. I just can't believe max loads are that slow. Are you showing any pressure signs on your brass? Is your brass covered with soot indicating a load that's too light? Maybe powder scale is off rather than the chrono? Make sure your scale is not affected by any source of wind like a ceiling fan etc. This can give heavier than normal readings. If electronic scale, how's the battery? Check it with a bullet or something of known weight.:confused:

hueyville
January 6, 2013, 10:27 PM
Made the switch to Hogdon CFE and not looking back. Say you are crimping the bullets.. Have all cases been trimmed to length? If not, every crimp is going to be exerting different tension on the bullet bases on un-uniform case length.

rg1
January 6, 2013, 10:51 PM
Either a chronograph error or powder weight error because 25.5 should get you to the 2800 range or above. Don't have any idea what else would cause such low velocity with 748 and 62 fmj's. You got good bullet tension in the case?

KansasSasquatch
January 6, 2013, 10:55 PM
25.5gr of 748 is above max according to Hodgdon data for the 62gr bullet they have on their website and is above max according to Lee's 63gr data. Have you tried dropping the charge? Maybe 748 needs a little more empty space in the case to start a complete burn? What COL are you seating to? Have you tried different primers? It might take a magnum primer to get those powders to ignite completely.

FROGO207
January 6, 2013, 11:57 PM
I would loose the crimp and try that for starters. I use Tac and the surplus pulled for it from Pats Reloading and get comparable velocity to MIL SPEC ammo with my 5.56 reloads. I also would double check that propellant weight and bullet weight if I were you. Something doesn't match up to specs for you for sure.

Hamish
January 7, 2013, 12:01 AM
Another factor to consider is the length of the barrel used for the test loads in your manual. If they used a 24" barrel, and you use a 20" barrel, you will most likely come in with a lower velocity round, all other factors being equal.

eam3clm@att.net
January 7, 2013, 10:04 PM
How much velocity spread did you have with the rounds? If they were all acceptable and close to each other and each shot of the wolf ammo was close to each other you can eliminate a chroney error. The fact that you also got low readings with two different powders reassures this theory with the infomation you provided.
I would first suspect your scale is off. What scales are you using? If you dont have a set of check weights, weigh a bullet. A 62 grain bullet should weigh close to 62 grains. There will be some varience, but the varience is velocity in what your actually getting and the manual sounds like it is more than a couple of grains. How does your cases look? Are they sooty? How well does the gun function, and what is the relationship in the ejection path of the wolf and your loaded ammo?
Also at what length did you seat the bullets? My THEORY on bottle neck cases and bullet seating deapth is that when you have a lot of empty case volume the powder does not burn efficently unless you add more powder to adjust. You have to be careful because you lose the running start that the bullet has into the rifling and can cause a pressure spike when it starts into the rifling. The readings on your chrony will show with a wide spread if your powder is not burning consistently. I have found this true more for slower for caliber/bullet weight powders than the faster powders. Like I said this is my THEORY based on MY testing. YMMV Compare your seating depth with the book value. I kind of doubt that this is the cause due to the large difference in velocity for what you get and the book.
A while back I ran some tests on some 223 ammo. I was like you and wanted to make a large production run of put away ammo. I was also using a ball powder. We have all heard at some point in time to use a magnum primer with ball powder, more so in cold weather (Its cold now). One of my books listed a regular primer while the other listed a magnum primer. I decided to run some tests with my chroney. It was summer so I had to make due with what I had, a freezer. I loaded a control that were left at room temp until I shot them, a batch that I left in the summer sun until I shot them, and some that were put in the freezer 30 min prior to shooting them. All of these were with a standard primer. The room temp load shot normal as well as the ones left in the sun, but they clocked a little faster. The ones that were placed in the freezer had really low velocity, and I had a few that hangfired.

The next group was with magnum primers and the rounds were stored in the same manner as above prior to shooting them. The room temp rounds were a little faster with mag vs standard primers. The freezer rounds all fired fine and velocity was close to the standard primer control at room temp. The rounds left in the sun with mag primers showed signs of pressure and the velocity showed that. This was a test I ran with my gun with my componets and loaded in the manner in which I load. YMMV

Henry45
January 8, 2013, 08:55 PM
Last check i did, i was shooting 55g Federal FMJBT, out of a S&W MP15 sport 16"bbl. Used 26g of 844 and was getting in the low 2800's consistently with the Chrony. I figure, if I figure correct, when i shoot these out of my Armalite with 20" bbl, i'll be pushing 2900-3000fps, which is just about what i'm looking for.

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