Confused about powder grains

[charlessummers]

I'm planning on loading 9mm, 115g FMJ. Here's what I've got...

 

Unique Powder, primers, cases, and 115g FMJ bullets that I bought at the Hendersonville show. I've read that it needs anywhere from 4.7grains of powder to 6.3 grains. How do I know what's the correct numbers? Of course this is all target rounds, and I do not want to blow up anything.

 

Alliant Powder website says 6.3 grains, based on Speer GDHP, but like I said... I'm using a FMJ. How does one go about figuring this out?

 

http://www.alliantpowder.com/reloaders/powderlist.aspx?page=/reloaders/powderlist.aspx&type=1&powderid=3&cartridge=23

[Raoul]

6.3 is the max load. That's pretty stiff. Using a lead bullet I load a 115 gr bullet at about 5.1 of Unique. It a good target load. For me at 4.7gr not all my pistols would cycle well.

[RED333]

You have to HAND load to get what works for your firearm, then you can RELOAD a lot.

[gregintenn]

What brand are the bullets? I'd go with the load data for them. Different bullets can have different overall lengths, when seated to the same overall cartridge length, can affect case capicity, therefore changing pressures even with the same powder charge. I wouldn't go by the Alliant recipe unless I were using the exact components listed. If you don't own a reloading manual, you should really get one....or two....or three.

 

I would suggest you start by loading a few at the minimum load and shoot them. Then, you can load a few more with an increased powder charge and shoot them. When you begin to see high pressure signs, back off some. If you reach the maximum listed load without pressure signs, stop there. Somewhere in this range, you'll likely find a load that shoots very well and functions well in your gun.

 

Next, you can start the process over with a different bullet, or powder, or both. Finding that perfect load is one of the best parts of reloading.

Edited January 23, 2013 by gregintenn

[AMSting]

I use 4.7 grains Unique for a target load.  It works fine in the XDm.  I use a Precision 115 grain bullet.

[Randall53]

Like the others stated, the low number is always the minimum amount of powder recommended by whatever reference you are using when working up a load for the first time. The higher number is the max and not the safe one to start with. I always start out very close to the low number, load 5 rounds or so and put them in a container with all info recorded on it. Then I do the same thing increasing the powder amount a little at a time, maybe half a grain or so. I hardly ever load to the maximum and usually don't find it to be the best load. I'll go to the range with a note pad and my homemade lots and evaluate each one for pistol performance and accuracy. Then, if you REALLY want to get crazy you can take the best load and tweak that up a little and down a little a couple of grains each time and repeat at the range. Some people will even weigh bullets and match them in like groups and start over...LOL. Reloading is a lot of fun and safe IF you use common sense and strictly follow the rules of safety.

[JRWnTN]

You really need to buy a reloading manual and not rely just on the powder manufacturer's booklet or website.  I started reloading when Jimmy Carter was president, using a Lee Loader.  I bought a Hornady manual and read and re-read it.

[gregintenn]

Like the others stated, the low number is always the minimum amount of powder recommended by whatever reference you are using when working up a load for the first time. The higher number is the max and not the safe one to start with. I always start out very close to the low number, load 5 rounds or so and put them in a container with all info recorded on it. Then I do the same thing increasing the powder amount a little at a time, maybe half a grain or so. I hardly ever load to the maximum and usually don't find it to be the best load. I'll go to the range with a note pad and my homemade lots and evaluate each one for pistol performance and accuracy. Then, if you REALLY want to get crazy you can take the best load and tweak that up a little and down a little a couple of grains each time and repeat at the range. Some people will even weigh bullets and match them in like groups and start over...LOL. Reloading is a lot of fun and safe IF you use common sense and strictly follow the rules of safety.

...and if you want to truly be anal about it, you can further tweak your load by trimming cases each loading, and seperating them by headstamp and then by weight. You can also tinker with different seating depths and amounts of crimp. You can go far as you want to go with it.

[charlessummers]

Ok now... let's not overwhelm the n00b.

[Raoul]

Simply put, start at the lower end and test your load by shooting it. Gradually increase the powder charge if you need to until you find a load within the range that works best in your gun(s),

Edited January 23, 2013 by Raoul

[Dolomite_supafly]

I generally start right in the middle of the load data. Then I go up or down until I find an accurate load they cycles. And in most cases the max loads are not the most accurate. I try to find the minimum load that will reliably cycle in all my guns.

 

Dolomite

[Guest Lester Weevils]

The OAL (overall length) of the loaded round, and the design of the bullet, interacts with the powder load. A hollow point at 115 gn and "proper" overall length to feed and cycle in the gun well, will typically take up a different amount of space inside the case, than a FMJ or other shape bullet of the same weight.

 

The amount of "free space" left in the case is important with a fairly fast powder like Unique, because it will get burning pretty good before the bullet starts moving. If one bullet style takes up more space inside the case, then that leaves less space in the case for the powder to burn in the first few microseconds, and POSSIBLY build up too much pressure, even though it would be fine with the same amount of powder with another style of bullet that takes up less space inside the case.

 

So ideally you would find a recommended OAL and min/max load for a FMJ bullet similar to what you are loading, and start near the minimum. Symptoms that will encourage you to slightly increase the powder load would be stovepipes (where the case doesn't completely eject but gets caught pointing upwards between the barrel and slide), and misfeeds, where the slide doesn't move far enough back to pick up a new round on its return to closed position.

 

Once you have increased from the minimum, a tenth of a grain at a time, until you have a round that will operate the gun 100 percent, you have the lightest practical target load FOR YOUR GUNS. When all my pistols were pretty weakly sprung, that very light load was also quite accurate and clean burning. But then I bought a couple of heavier-sprung 9mm guns that wouldn't work 100 percent on those light loads, and I didn't want to load two different recipes, a light load and medium load, so I upped the load until it would operate the new stiffer guns along with the older lighter-sprung guns. It was a "new stronger minimum load" with enough ooomph to operate all the pistols.

[Jamie Jackson]

What brand are the bullets? I'd go with the load data for them. Different bullets can have different overall lengths, when seated to the same overall cartridge length, can affect case capacity, therefore changing pressures even with the same powder charge.

 

 

This is a good point.

 

I generally use Berry's Bullets for my Glock's...9mm.

 

I e-mailed Berry's to get their recommendations as to Overall Length for their bullets. Most companies have this data and are more than willing to provide it to you.

 

A rule of thumb is to take the "max load" and reduce by 10% as a starting point...at least that's worked for me when I only had "max" load data available.

Like others have said, find the bullet, powder, OAL combination that works best in your gun.

 

A good manual or two, well read, is your best friend.

 

 

btw: Berry's 9mm

124 RN is 1.160, the 124 FP is 1.060, and the 147 is 1.160.

[frankmako]

low number is min.  high number is max.  when i load something new i start at max less 10%.  this get me in the ball park.  i load ten rounds and run them across my chronograph to see what the are runing.  then i work from this point up or down to come as close to the factory round.  i shoot several factory rounds to get a base line for the gun first.  for cast lead bullets i reduce the loads to stop leading and to have more fun at the range.

[2006Blackpearl931]

You can also visit www.reloadersnest.com for some recipe ideas. Just to give you some comparison, I load 147gr moly coated lead 9mm, and only use 3.3 gr of Unique. Shooting an M&P for IDPA and 3gun. So far, this has been very reliable for me. SO, the other members are right in suggesting you have to find a load that is safe and reliable, and is tailored to your needs.

[Dolomite_supafly]

low number is min.  high number is max.  when i load something new i start at max less 10%.  this get me in the ball park.  i load ten rounds and run them across my chronograph to see what the are runing.  then i work from this point up or down to come as close to the factory round.  i shoot several factory rounds to get a base line for the gun first.  for cast lead bullets i reduce the loads to stop leading and to have more fun at the range.

Leading is more than just velocity. I push cast bullets a lot faster than most pistols and have no leading problems.The majority of leading problems is caused by one of two things. Either the bullet is too hard to obturate or the bullet is too small allowing gas to cut past the lead bullet. Most commercial cast bullet makers do both. A cast bullet NEEDS to be at least .001" but ideally .002" above the bore diameter to stop the leading. And the bullet needs to be reasonably soft to properly squish and seal to the bore.

 

A lead bullet can be .003" or even .004" over the bore diameter and it will just get squished down. And with lead you do not get the same pressures as with jacketed. I have shot bullets that were .00485" over the bore diameter and had zero problems.There is nothing to gain by using a bore sized cast bullet but a lot to gain by using one that is oversized.

 

If a person is getting leading at the chamber end of the barrel it is caused by a bullet that is either too hard or too small or both. If you are getting leading at the muzzle end of the barrel it is from being too fast but honestly I rarely see that in pistol calibers. Proper lube can mitigate leading at the muzzle end but no amount of lube will fix leading at the chamber from a bullet that is too hard or too small.

 

For my 45 ACP I try to make sure the cast bullets are .452". For my 300 Blackout, which has a .308" bore I run a .310" cast bullet. For my 9mm, which has a .355" bore, I use a .358" cast bullet.

 

Dolomite

[Jamie Jackson]

Excellent info Dolomite. Thanks.

 

I'm just starting to reload lead 147 gr bullets for my Glock 17 (just picked up a Lone Wolf barrel- Thanks Caster! :up: ).

 

My goal is to start casting my own. The info here has proven invaluable!

[Raoul]

Excellent info Dolomite. Thanks.

 

I'm just starting to reload lead 147 gr bullets for my Glock 17 (just picked up a Lone Wolf barrel- Thanks Caster! :up: ).

 

My goal is to start casting my own. The info here has proven invaluable!

 

I really like the 147gr. It's my favorite load.

[Jamie Jackson]

I really like the 147gr. It's my favorite load.

 

 

I'm heading to the range in about an hour. we'll see how it goes. I got hopes! :pleased:

[geekitupsum]

I use 5.5gr of unique with 115gr fmj 9mm. seems to work well

[JeffL]

Step 1 is buy a reloading manual. The Speer manual was very informative. I ended up buying the Lyman manual as well for additional data. Have considered buying a few more.

[QuietDan]

Step 1 is buy a reloading manual. The Speer manual was very informative. I ended up buying the Lyman manual as well for additional data. Have considered buying a few more.

This times a 1000.

 

I too started with the Speer manual, very well written.

 

Read all the front information, and all the cartridge information for the cartridges you will be reloading. Read it all several times and understand it before you start reloading.

 

Then, you will be safe and know why you are safe, and you will be successful, and know why you are successful.