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OK I'm new to reloading i have a concern. I ordered my bullets they are Hornady GMx .308. Im using a federal brass shell. my question is that the soft points that are orginally in the factory bullet is a soft point which is shorter than the length of my GMx bullets. Will it Matter if my GMX bullet are seat deeper inside the shell due to the length of it.
The Hornady GMX bullet is 1.424 inches
The Factory bullet is 1.117 inches
If anyone could help me i would apperiate it .
You are right, your round has to have a OAL, longer bullets must seat deeper.
Thank you I was just worried that it would mess my rifle up
Many longer/heavier bullets require seating with the bullet's base well below the bottom of the case neck. What loading manuals do you have? (You should have a MINIMUM of three current manuals - world's most inexpensive life insurance.) The Hornady manual should list their recommended OAL for that bullet/cartridge, and you can probably find it on their website, too.
When in doubt, start with the manufacturer's suggested OAL until you have tested and found the optimal charge of the powder you have selected. Then you can start playing with seating depth to fine tune the load. Due to the different nose profiles of different bullets, the optimal OAL for your rifle will also be different for each. Pressure is always lower and accuracy is often improved when you can seat to a longer OAL, but just how much longer depends upon the design of both your rifle's magazine and chamber. For a large game hunting rifle it is not usually a major issue, but for a varmint or target rifle it can be.
What I think I would do is take a fired round and slightly squeexe the neck so that it will hold a bullet and seat a bullet so that it will just fit in the magazine. Then I would carefully chamber that dummy round with the bolt removed, using a wood dowel or similar tool to push the shell int the chamber. The bullet should be pushed deeper into the shell when it engages the rifling. This should give you a starting point on how deep to seat the bullet. You should be very careful removing it from the chamber so as to not change where the bullet was seated. That's if your rifle is a push feed type. If your rifle has controlled feed, you can remove the bolt, place the cartidge undr the extractor and very carefully chamber that dummy round. Carefully remove it and measure. When setting up the seating die, seat it just a bit deeper so that the bullet does not hit against the rifling.
The Hornady #8 manual gives a generic 3.340" at the cartridge overall length as is used for all their bullets. No mention of the GMX bullet in my copy. Later printings of the #8 may show something different but I wouldn't bet on it.
Your best bet would be to either call or E-mail Hornady for their suggestions. That's what I would do in your case.
Paul B.
[QUOTE=versifier;9898]Many longer/heavier bullets require seating with the bullet's base well below the bottom of the case neck. What loading manuals do you have? (You should have a MINIMUM of three current manuals - world's most inexpensive life insurance.) The Hornady manual should list their recommended OAL for that bullet/cartridge, and you can probably find it on their website,
I have the lee manual
IMO, one manual just doesn't cut it from a safety point of view. People make mistakes, and some of them do it while entering data. If the one manual you have has such an error, how can you know before it's too late? Or, what if (as is quite common) you have only two manuals and they do not agree on START and MAX loads with the same weight bullet and the same powder? (Different lots of components and different firearms always yeild different data even when you try to "do it the same way".) With three manuals, two will almost always come very close to agreement. Likewise, how can you evaluate data from a questionable source (i.e. found online) without more than one opinion to confirm or deny its safety?
Lee is a good manual (there is a copy on my bench), but do be aware that they don't do any of their own testing, it's all copied from other sources. But, like Lyman (who does all of their own testing), it has a ton of data for many different brands and weights of bullets for each listed cartridge, including cast rifle data, that are not found in more selective sources. Lee, Lyman and one from your favorite bullet maker are a good combination to rely on. The bullet maker's manual will have specifics on all of their bullets like OAL for appropriate cartridges, sectional density, and ballistic coefficients necessary when you have to do serious calculations or need to make the best bullet choice for a specific application.
Never rely on just one reloading manual.
i use the lee manual to see if the data even exists.
then i go and find it.
different bullets will raise or lower pressures also [mainly because of jacket thickness]
if you have an all copper bullet or a thick jacketed regular one,and use data for [say a sierra] you can be in trouble even though you followed the recipe.
lee's manual is too general for me.
oal is established by the rifle and what will feed through it, you might have to slightly lower or increase the powder amount to compensate. for the case volumn loss or gain.....
"Or, what if (as is quite common) you have only two manuals and they do not agree on START and MAX loads with the same weight bullet and the same powder? "
Quite true. However, most starting loads should be reasonably close to being the same so should not be a problem. With some experience and careful measurment practices along with a chronograph, then one should be able to work up to the safe max for their rifle.
FWIW, due to personal experience I no long trust some of the data in the Lyman Manual. For many years I had a pet load that I woked up to from that manual, #44 IIRC. circa 1967. It showed pressure data in C.U.P. as the method of determining pressure. The current #49 manual shows that exact same data, still with the C.U.P. figure for pressure. Lyman book #49 is circa 2008. I find it hard to believe that they have not retested that data in 41 years. For one thing, IMR powders were made by Du Pont back then and now they're being made by a company using IMR as their name. I've heard tell that they quit using cotton linters for their cellulose, going to sawdust dissolved in nitric acid insstead as the cost was less. Just that alone would make me suspect of older data with the IMR powders (Du Pont vs IMR manufacture.)
Just another point. The Lyman #43 manual gives a starting load for 4895 )Type not specisfied but probably milsurp is my guess) of 49.0 gr. with a 150 gr. bullet in the 30-06 with a max load of 54.0 gr. A few years back, I loaded some IMR4895 under the 150 gr. Sierra Pro-hunter. That was my pet deer load for over 20 years until I got tired of that bullet ruining too much good meat if one of my shots wasn't quite right. The load was fired in the very same rifle I'd used all those long gone years. The bolt was solidly locked up on the first round and I'm thinking, "Did I screw up with the powder measure?" I broke the rest of that ammo down and check weighed each charge on a balance beam and then on a digital scale. All loads checked out ay + or - one tenth of a grain. That ammo was all spot on. That load BTW is at the half way point in the current Lyman manual. Now I'm sure Lyman must feel that load data is OK but once burned, twice shy sez I and I take their data marked C.U.P. for pressure with a copious quantity of salt. Their data marked P.S.I. has apparently been shot with more modern equipment as I'm not so leery of it. The problem was probably my fault in assuming 4895 hadn't radically changed. I really should have known better but all I was trying to do is see just what did that load do regarding velocity. There weren't any affordable chronographs back in 158 or 9 when I first worked up that load. I used it for deer with great succes until 1971 when a friend convinced me to try 180 gr. bullets in order to reduce meat damage.I went to the Sierra 180 gr. Pro-Hunter and never looked back.
Paul B.