Can someone please help


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Ruger GP100 fan
November 30, 2010, 05:04 AM
I'm loading for a 22-250. I'm new to reloading having just bought a press this past summer. I've been fighting the same problem since day 1 with not being able to hold consistent OALs. Tonight,for example,I loaded 20 rounds of once-fired brass(I know because I bought and shot it)and I very meticulously prepared each piece before starting to reload I seated the first round at 2.354 and did not change anythig. Next round was 2.358...set it aside. Next round was 2.358...set it aside. In the past I have been chasing the length by re-adjusting the stem with miserable results,so I decided to continue reloading all 20 rounds without touching the die. When I was done I had 8 rounds at 2.354 +/- <.0005, 11 rounds at 2.358 +/- <.0005 and one oddball right smack dab in the middle at 2.356. So,I guess you could conclude that my results are consistently inconsistent. My bullet choice was 52gr Hornaday A-Max BT# 22492 designed specifically for the 1:14 barrel in my fifle,but I have the same problem with every bullet I've tried,including a number of hollow-points from differing makers. Folks,I have removed the seating stem,chucked it into my cordless drill and polished it to the best I can get,starting with 600grit cloth to 1000grit,all the way down to 00 steel wool with no improvement. The argument that my rifle is only a factory gun is totally beside the point. This problem is incredibly frustrating for me. If the measurements were all over the place it would be different and perhaps attributable to my low-end equipment,but as I pointed out above,the measurable differences seem accurate to some degree with basically 2 groups of identical OAL and that the differences were not consecutively loaded suggesting something other that a setting suddenly moving on me. Any suggestions?

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Ruger GP100 fan
November 30, 2010, 05:12 AM
Wanted to add that I've seen posts of targets where the load data listed a COAL of a very specific dimension at 3 decibel points. In all honesty are you achieving this on every round?

Grumulkin
November 30, 2010, 07:54 AM
1. If you are measuring cartridge overall length by measuring to the tip of the bullet then stop it. You have to measure to some point on the bullet that won't be different dimensionally like the bullet ogive. If you measure to the bullet tip you will be frustrated for the rest of your life since all bullets you can buy vary slightly in length; even match bullets. Sinclair sells some bullet comparitors with which you can use your dial calipers to measure from the cartridge head to the ogive.

You also don't mention what kind of accuracy you're getting. If your accuracy is satisfactory, you probably don't need to agonize over a few thousandths of an inch.

2. Three "decibel points?" I think you meant 3 decimal points. In all honesty, I don't even check. I load most cartridges with the bullets almost at the lands providing that such lengths will allow feeding through magazines, etc. I would say what probably happens is the targets you refer to have an average COAL listed from several cartridges measured. Depending on what instrument is used to measure, the third decimal place number is probably open to question.

rattletrap1970
November 30, 2010, 08:21 AM
Well, for one thing you shouldn't measure to the tip or "meplat" of the bullet as they have some variance because of shipping and such. They get dinged, flattened, etc. You should get a tool (I believe Hornady makes) that attaches to your vernier calipers. It has different inserts and measures the base of the case to the ojive of the bullet. But to be honest, the seating depth (a couple of thousandths difference) is less critical than the resized, and fully prepped brass all weighing the same. Because obviously if all of the outer dimensions are the same, then the only variance can be the inner volume. And if that is different your pressures will be all over the place and so will your accuracy. Neck tension is important also as this effects your pressures too.

Get the Hornady measuring attachment and a neck outside trimmer.
Make sure your prepped brass weighs the same amount within 1 grain.
Make sure your neck thicknesses are the same

cfullgraf
November 30, 2010, 08:52 AM
There always be some variability in the overall length but as stated measuring off the tip will give the greatest.

Sinclair International as several different tools for measuring off the ogive including the Hornady version.

Most, if not all, bullet seaters seat the bullet off the ogive.

As a side note, I have found that as I am setting up my seating depth, I get different measurements when I adjust the bullet seater by small increments versus when I seat to the final depth in one stroke.

So, once I have the seater close, I will seat a new case and bullet, measure, make an adjustment, then seat a new bullet and case and measure this round. I don't chase my tail so much when seating up the seater.

Hope this makes sense.

243winxb
November 30, 2010, 10:23 AM
Common to have .005" to as much as .010" variance. Lee Info> Seating depth variations

There are a number of possible causes for overall length variation. One is the way it is measured. If you measure overall length from the tip of the bullet to the base of the case, remember to subtract the variation due to bullet length tolerance. The bullets will vary in length due to manufacturing tolerances (bullets with exposed lead noses are the worst in this regard) and this will add to the overall cartridge length variation. Remember that the bullet seater plug does not (or shouldn't) contact the tip of the bullet when seating, but contacts farther down the ogive. For a more accurate seating depth measurement, take the seater plug out of the bullet seating die, place it on top of the cartridge and measure from the base of the case to the top of the seater plug.

Another possible cause for bullet seating depth variation is seating and crimping at the same time when trying to apply a firm crimp to untrimmed cases. Variation in case length also causes variation in the amount of crimp applied. Long cases get a heavier crimp than short ones. When seating and crimping at the same time, the crimp is formed as the bullet is seated into the case. The crimp will form sooner on a long case, and therefore the bullet will not be seated as deeply. The solution is to seat and crimp in a separate step (the Lee Factory Crimp die is good for this) and/or trim cases to a uniform length.

The amount of force required to cycle a progressive press varies with the number of cases in the shell plate. When the shell plate is full, it is harder to lower the lever than when there are one or two cases present. This can lead to variation in cartridge overall length because there are different loads placed on the working parts of the press. When the shell plate is full, seating depth will be slightly long, because the load is higher and all of the clearances are taken up. With the shell plate nearly empty, the load is not great enough to squeeze out these clearances, and the seating depth is short.

From Reddings Tech Line Tips
[/COLOR]

Seating Depth Variation
There are many factors that can cause bullet seating depth to vary when using our Competition Seating Die. First, make sure you're comparing bullet seating depths correctly. You cannot check bullet seating uniformity by measuring cartridge overall length off the bullet point. You must use a bullet comparator, like our Instant Indicator, to compare bullet seating depths. A comparator contacts the bullet at the bore diameter contact point. This is important, as bullets can vary slightly in overall length.
We have designed the seat stem in our Competition Seating Die to contact the bullet ogive as far down as possible. Our Competition Seating Die features a bullet guide that is only .0005-.001" larger than bullet diameter. This tight fit between the bullet guide and bullet ensures that the bullet is seated straight in the case neck. It also limits how far down the ogive the seat stem can contact the bullet. If the ogive of your bullets aren't uniform, you may notice a slight difference in seating depth. Generally, this isn't a problem as modern bullets are very uniform. In rare instances, when using inexpensive bulk bullets, you may find that the bullets were made on several different machines and then blended.

If your loading press is worn, the ram may not stop in exactly the same spot each time you raise it. Obviously, this will cause variations in bullet seating depth. Although our instructions warn against it, raise the shellholder and adjust the outer, threaded die body to make light contact with the shellholder. (Make sure you keep the contact light, so you don't damage the die.) This creates a "dead length" seating chamber that is unaffected by where the shellholder stops. The only disadvantage to using the die adjusted this way, is that it may be awkward to read the micrometer if it ends up on the back side of the die.

Inadequate or excessive neck tension can also cause bullet seating depth variations. If you're using a bushing style sizing die, make sure you've selected the correct diameter bushing to size the case necks. Our current recommendation, is to select a bushing tha t is .001" smaller than the neck diameter of your loaded cartridges. (See the bushingselection newsletter in the "Tech Line" section of our website for more information.) As cases are fired over and over, their necks become progressively harder. This can cause the necks to "spring-back" excessively when they are sized, which reduces the neck tension on the bullet. Either anneal the case necks after several firings, or discard the cases and start with new, soft ones.

Heavily compressed loads can create problems when seating bullets. Our Competition Seating Die is not a powder compression die. The excessive force required to seat a bullet on a compressed load can damage the die and may cause seating depth variations. Switching to a faster burning or ball powder may eliminate the need to excessively compress the powder charge.

If you have any further questions, please feel free to call our technical support line at 607-753-3331 607-753-3331 .
]

grubbylabs
November 30, 2010, 10:55 AM
Wow thanks OP for asking and every ones responses I too have had the same issue and have been loading since spring as well. Nice to know Its not that I am necessarily doing something wrong other than measuring from the wrong spot.

Ruger GP100 fan
November 30, 2010, 03:15 PM
Thank you all for your input...I can stop pulling out what hair I have left. I suppose I should be glad I'm getting any consistency at all considering I'm just using RCBS's standard 2-die set,because,aside from the 1 round, the 2 groups are literally withing .0005 of each other and I am not set up to turn or ream necks,or is it just pure blind luck? I've even been going to the extra trouble of dragging the flat base of the case on a piece of 600 grit paper in an effort to find consistency. So,for my factory Ruger M77...would there be any benefit at all in measuring bullet length before loading and then grouping them in lots of the same length so that bullet tip to barrel is equal,that is,after I buy and learn to use the proper seating die? In BR competition is this difference in bullet length a concern such that loaders,while using competition dies and seating to an exact point on the ogive,still have differing bullet lengths to deal with measure them and use all one length to compete?

Grumulkin
November 30, 2010, 05:08 PM
I think you're a bit too concerned about cartridge length and your RCBS standard 2 die set should be fine for your purposes. My procedure for determining my COAL is:

1. If the cartridge needs to be shot from a rifle with a magazine, I seat the bullet as far out as possible while still giving reliable feeding from the magazine. I also make sure enough bullet is in the neck of the case to ensure it being gripped firmly.

2. If possible, I seat all bullets except Barnes bullets so that they're just off the lands when chambered as long as the criteria in #1 are fulfilled. You can chamber a cartridge and see scuff marks on the bullet which will tell you where the lands are. Some will smoke bullets to make visualization of the scuff marks easier but I don't.

I have at various times durned necks, uniformed primer pockets, cleaned primer pockets and deburred flash holes but no longer do because I couldn't see any accuracy advantage in firearms I was shooting. Maybe if I had a dedicated bench rest gun capable of sub 0.25 MOA I would notice a difference but I don't in what I shoot.

243winxb
November 30, 2010, 06:35 PM
...would there be any benefit at all in measuring bullet length before loading and then grouping them in lots of the same length so that bullet tip to barrel is equal, The bullets bearing surface is more important then length. Just buy good match or target bullets and you need not worry or measure. If shooting 1000 yards then maybe. Your sizing die is what can cause the bullet to seat crooked or have runout. Look at the Redding Type-S FL Bushing Dies. Then maybe a bullet seater. I am no benchrest shooter, but using a standard RCBS seating die has worked well for me. Other will have there own method of loading, all may work with the right firearm. The proof is on the target. Read this, might help. http://findarticles.com/p/articles/mi_m0BQY/is_4_48/ai_83483904/

mallc
November 30, 2010, 07:42 PM
Most, if not all, bullet seaters seat the bullet off the ogive.

Are you sure about that??

Scott

rfwobbly
November 30, 2010, 07:52 PM
Quote:
Most, if not all, bullet seaters seat the bullet off the ogive.

Are you sure about that??

Scott

Most rifle dies push on the ogive because they don't know if you have a hollow point, soft point, or no point at all.

Most pistol dies push directly on the nose of the bullet, either with a concave or flat seating anvil.

The OP was talking rifle, so the responses focused on rifle bullet seating without directly saying so.

Hope this helps!

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