The Firing Line Forums - View Single Post

noylj · February 7, 2017, 05:27 PM

>New to reloading.. started with 40s&w..

Couldn't start with something "easier," like 9x19 or .45 Auto?

>I started low and worked up a few grains.

I hope you mean a few tenths of a grain. Not many .40 S&W loads cover several grains.

>Made about 10 rounds of each load...they all shot and grouped fine..

Define "grouped fine." Did any show any pressure signs? So far, sound good.

>so my question is when do I decide to just keep loading to that"one" recipe?? Im just shooting paper. I was loading off brand 180grain rnfp.. so I made my oal longer then books said because I didn't want to overppressure (checked with gun barrel).didn't trim cases either.

>Good. The COL in a manual is what they used for testing and is NOT what you should be using. Next, you never need to trim staightwall cases and cases that head space on the case mouth should be as long as possible to minimize "head space" and increase accuracy.
Per Ramshot:
"SPECIAL NOTE ON CARTRIDGE OVERALL LENGTH “COL”
It is important to note that the SAAMI “COL” values are for the firearms and ammunition manufacturers industry and must be seen as a guideline only.
The individual reloader is free to adjust this dimension to suit their particular firearm-component-weapon combination.
This parameter is determined by various dimensions such as
1) magazine length (space),
2) freebore-lead dimensions of the barrel,
3) ogive or profile of the projectile and
4) position of cannelure or crimp groove.
• Always begin loading at the minimum ‘Start Load.’"
(ed. I take that to mean to check several sources and to start with the lowest start load)

Your COL is determined by your barrel (chamber and throat dimensions) and your gun (feed ramp) and your magazine (COL that fits magazine and when the magazine lips release the round for feeding) and the PARTICULAR bullet you are using. What worked in a pressure barrel or the lab's gun or in my gun has very little to do with what will work best in your gun.
Take the barrel out of the gun. Create two inert dummy rounds (no powder or primer) at max COL and remove enough case mouth flare for rounds to chamber (you can achieve this by using a sized case—expand-and-flare it, and remove the flare just until the case "plunks" in the barrel).
Drop the inert rounds in and decrease the COL until they chamber completely. This will be your "max" effective COL. I prefer to have the case head flush with the barrel hood. After this, place the inert rounds in the magazine and be sure they fit the magazine and feed and chamber.
You can also do this for any chambering problems you have. Remove the barrel and drop rounds in until you find one that won't chamber. Take that round and "paint" the bullet and case black with Magic Marker or other marker. Drop round in barrel (or gage) and rotate it back-and-forth.
Remove and inspect the round:
1) scratches on bullet--COL is too long
2) scratches on edge of the case mouth--insufficient crimp
3) scratches just below the case mouth--too much crimp, you're crushing the case
4) scratches on case at base of bullet--bullet seated crooked due to insufficient case expansion (not case mouth flare) or improper seating stem fit
5) scratches on case just above extractor groove--case bulge not removed during sizing. May need a bulge buster.

>Started with 4.6gn universal
>180gn plated rnfp
>1.175 oal

Being a plated bullet, you should almost always use lead bullet data.
I show start load of 3.8-4.7gn for 180gn lead bullets and Universal, with MAX loads of 5.1-5.7gn, so you started higher than I would have.
Some manufactures for their heavy-plated bullets say to use jacketed data, in which case they almost always say to go up to mid-range, then I show 4.2gn as a starting load and 4.7gn as being mid-range.
For FP bullets, I normally load to a COL of ~1.200" for my three .40s, but it all depends on the bullet and chamber.

>Then stepped up to 4.7 and 4.8 grains..all shot reliable and grouped better then I can shoot..

That is a very small increment to step up with. Unless loading just for a power factor, I normally take the range of charges (let's say 3.8-5.1gn) and step up from start to max to cover 5 or 6 steps (say 3.8, 4.1, 4.4, 4.7, 5.0gn) and see what I get. This is much more likely to quickly show where the real accurate load is than taking 0.1gn steps.

>the 4.8 grains flattened the bullet the best on my backstop.

Is that a goal? If so, as you go up in powder, the bullet will probably be flattened even more.

>So I don't think I'll go any lower then that. But what about going up in grains? Should I just leave it where it is at and shoot em? Or is there a benefit to trying a few more grains of powder? Thanks ...hope I made sense...

A few TENTHS of a grain more powder might give better accuracy--who knows. However, right now, you are happy with the accuracy and the gun is functioning, so load some more and have fun.

February 7, 2017, 05:27 PM	#5
noylj Senior Member Join Date: October 21, 2007 Location: Between CA and NM Posts: 858	>New to reloading.. started with 40s&w.. Couldn't start with something "easier," like 9x19 or .45 Auto? >I started low and worked up a few grains. I hope you mean a few tenths of a grain. Not many .40 S&W loads cover several grains. >Made about 10 rounds of each load...they all shot and grouped fine.. Define "grouped fine." Did any show any pressure signs? So far, sound good. >so my question is when do I decide to just keep loading to that"one" recipe?? Im just shooting paper. I was loading off brand 180grain rnfp.. so I made my oal longer then books said because I didn't want to overppressure (checked with gun barrel).didn't trim cases either. >Good. The COL in a manual is what they used for testing and is NOT what you should be using. Next, you never need to trim staightwall cases and cases that head space on the case mouth should be as long as possible to minimize "head space" and increase accuracy. Per Ramshot: "SPECIAL NOTE ON CARTRIDGE OVERALL LENGTH “COL” It is important to note that the SAAMI “COL” values are for the firearms and ammunition manufacturers industry and must be seen as a guideline only. The individual reloader is free to adjust this dimension to suit their particular firearm-component-weapon combination. This parameter is determined by various dimensions such as 1) magazine length (space), 2) freebore-lead dimensions of the barrel, 3) ogive or profile of the projectile and 4) position of cannelure or crimp groove. • Always begin loading at the minimum ‘Start Load.’" (ed. I take that to mean to check several sources and to start with the lowest start load) Your COL is determined by your barrel (chamber and throat dimensions) and your gun (feed ramp) and your magazine (COL that fits magazine and when the magazine lips release the round for feeding) and the PARTICULAR bullet you are using. What worked in a pressure barrel or the lab's gun or in my gun has very little to do with what will work best in your gun. Take the barrel out of the gun. Create two inert dummy rounds (no powder or primer) at max COL and remove enough case mouth flare for rounds to chamber (you can achieve this by using a sized case—expand-and-flare it, and remove the flare just until the case "plunks" in the barrel). Drop the inert rounds in and decrease the COL until they chamber completely. This will be your "max" effective COL. I prefer to have the case head flush with the barrel hood. After this, place the inert rounds in the magazine and be sure they fit the magazine and feed and chamber. You can also do this for any chambering problems you have. Remove the barrel and drop rounds in until you find one that won't chamber. Take that round and "paint" the bullet and case black with Magic Marker or other marker. Drop round in barrel (or gage) and rotate it back-and-forth. Remove and inspect the round: 1) scratches on bullet--COL is too long 2) scratches on edge of the case mouth--insufficient crimp 3) scratches just below the case mouth--too much crimp, you're crushing the case 4) scratches on case at base of bullet--bullet seated crooked due to insufficient case expansion (not case mouth flare) or improper seating stem fit 5) scratches on case just above extractor groove--case bulge not removed during sizing. May need a bulge buster. >Started with 4.6gn universal >180gn plated rnfp >1.175 oal Being a plated bullet, you should almost always use lead bullet data. I show start load of 3.8-4.7gn for 180gn lead bullets and Universal, with MAX loads of 5.1-5.7gn, so you started higher than I would have. Some manufactures for their heavy-plated bullets say to use jacketed data, in which case they almost always say to go up to mid-range, then I show 4.2gn as a starting load and 4.7gn as being mid-range. For FP bullets, I normally load to a COL of ~1.200" for my three .40s, but it all depends on the bullet and chamber. >Then stepped up to 4.7 and 4.8 grains..all shot reliable and grouped better then I can shoot.. That is a very small increment to step up with. Unless loading just for a power factor, I normally take the range of charges (let's say 3.8-5.1gn) and step up from start to max to cover 5 or 6 steps (say 3.8, 4.1, 4.4, 4.7, 5.0gn) and see what I get. This is much more likely to quickly show where the real accurate load is than taking 0.1gn steps. >the 4.8 grains flattened the bullet the best on my backstop. Is that a goal? If so, as you go up in powder, the bullet will probably be flattened even more. >So I don't think I'll go any lower then that. But what about going up in grains? Should I just leave it where it is at and shoot em? Or is there a benefit to trying a few more grains of powder? Thanks ...hope I made sense... A few TENTHS of a grain more powder might give better accuracy--who knows. However, right now, you are happy with the accuracy and the gun is functioning, so load some more and have fun.