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Flat point vs round point


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I guess after reading the posts in this string I'm confused about one thing which was said and that was "you have to load FN shorter than RN". I did not change bullet seating die for FN I kept it the same as my RN. The OAL for FN is 1.10 but the FN bullet is .035 inches shorter than my RN so I should end up having the same gas volume inside the bullet for RN vs FN. So its a shorter on the outside and the same on the inside.

I would guess this is because the shoulders of the RN vs FN contact the die at roughly the same point (Montana Gold FN vs Berry's RN) hence they are seated to the same depth in the cartridge but the OAL's are different.

In this this string someone talk about the drop and spin test, what's that?

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You need to know the length of the bullets themselves.

Get out your dial calipers and measure the length of one of each, RN and the FN, and they must be the same weight bullets. The difference in length is how much difference there needs to be in the OAL to maintain the same volume inside the case. The shorter bullet needs a shorter OAL to match the chamber volume of the longer bullet. That way you can use data for a RN when you don't have data for an FN. But the data is only valid for the same weight bullets.

If for some reason your FN and RN's have the same length of just the bullet you use the same OAL for both but this isn't very likely

Setting of the seat die is only relevant to the OAL, I actually use the RN seat in my Dillon die on a Flat nose bullet. Fits the bullet better than the Wadcutter side of the seater. I tried a flat seater in another die and wasn't happy with how things were turning out.

The reason you will often get a deeper seat of a flat nose without changing the die setting is that the edges of the bullet tip contact the sides of the seat die sooner than the round nose. But don't rely on this to be the correct set up for your bullets. Bullets are all different so you will more than likely have to change the set up between different bullets.

If the FN's just happen to seat at the needed depth for the difference in the length compared to an RN you are good to go.

Shoulder of the bullet is mostly referring to where it contacts the case, usually not an issue unless the bullet shape differences create a feed or chamber issue. This can become a problem with lead plated bullets as overcrimping them often bulges the bullet and causes chambering issues, one of the reasons for the Drop and Spin test or the Plunk test.

"Drop and spin test" is just a way to confirm your set up on your press is correct. But only do this with your barrel if you have removed it from the gun. In a perfect world every round off your press should just drop into the chamber and have just enough room to be spun by hand. If you don't have a chamber checker, they are cheap and worth the money, take the barrel out of your gun and you can do drop and spin tests on random rounds. The other name you might run across is "plunk tests". Rounds that are correct just slip into a barrel or chamber checker with a gentle plunk.

If in doubt ask more questions...

Edited by TonyK
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The drop and spin is when you remove your barrel from the gun and then drop a bullet in it and spin it with your finger. Some also call it the plunk test. The bullets go plunk when they drop in if the bullet is not too long.

I tried 9mm FP 147's in my new 1911 and they will not feed at all. I have to use RN. The FN are more prone to getting hung up when feeding in a 1911.

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Chris

I feed nothing but FP's to my 1911's, feed problems were all related to OAL. I load them extremely short (for a 45 anyways) and this solved my feed issues.

Doing so may or may not work with a 9mm 1911...

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I tried to load them short and they were still getting stuck in the throat of the barrel. It may very well have to do with the diameter of the bullets since the 9mm are so small compaired to the 45. The RN feed with no issues at all.

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Ok here are the results of my chrono tests of 9mm 147 grn RN Berry vs FN Montana Gold 147 grn. Pistol was a G17 with Storm Lake Barrel. First for 22 rounds of FN I had no failures to feed, which I was worried about. Both my RN and FN 9mm rounds were loaded with 3.8 grns of Winchester 231 misc brass and Winchester SP magnum primers. I am loading for a low PF around 130.

RN OAL is 1.14 and FN OAL is 1.10, however the length of the FN is .035 shorter than the RN, so while the OALs are different the space for the gas volume is just about the same. Note they were both loaded without changing the die setting on the bullet seating die.

Round Nose (fps) Flat Nose (fps) note: %SD is sd/ave expressed as a %

Test 1 Test 2 Test 1 Test 2

Hi 960 968 968 1031

Low 920 922 914 906

Ave 935 943 940 941

ES 40 46 54 125

%SD 1.2 1.2 1.8 3.5

shots 11 11 11 11

So it looks like I will have no problems with the FN at the same reloading settings as that for my RN, although the perception is I am reloading the FN to a shorter OAL.

Regards

Edited by Quag
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It's not really a perception, you are loading to different OAL. OAL is only an external measurement. Just because you didn't have to change the die set up doesn't mean it is the same OAL.

But glad things worked out for you...

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It's not really a perception, you are loading to different OAL. OAL is only an external measurement. Just because you didn't have to change the die set up doesn't mean it is the same OAL.

But glad things worked out for you...

good point on the OAL definition, and you are right. BTW a 1.10 OAL on my FN is not very different for 9mm I believe that's the OAL recommended for a lot of 115 and 125 grn bullets so from an external measurement perspective a 1.10 OAL 9 mm bullet should feed into a glock just fine. But its nice to prove it.

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Wow! What is the first thing to do. What is the most important thing to do? What to do to take all things into concideration.

1. Is COL important for accuracy and pressure? From what I gather, find the maximum COL for the particular bullet you are using by measuring it in the loading chamber and set it back about .01 to .02. Now, does this length function in your magazine?

2. What is the seating depth and how does it compare to what you have been using. This is a combination of COL and bullet length. If compared to your favorite load the seating depth is less, then so is presssure and visa versa. So you may want to change the charge of power you have been using.

3. I have no idea why the data in the books gives us COL without mention of the bullet (except Lyman). The more important measure is surely the seating depth. It's a corporations way of being vague enough to prevent law suits.

4. Conclusion: each change in bullet shape, given even the same weight, requires a change in COL and charge. But that's what it's all about..the challenge.

(dxxm, there is no spell check, so sorry for the misspells)

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About #2

COL is nothing more than an external measurement of a finished cartridge. Seat depth is determined by what will run in your gun or possibly other factors such as trying to increase pressures or even reduce the powder charge and still maintain the same pressures/velocity. Bullet shape is the primary determining factor of COL. I doubt there is a gun out there that will use the same COL for all bullet types.

About #3...

Every load manual I have or have data from (Sierra, Hornady, Speer, Nosler, Western Powder, Vihta Vouri, Alliant etc ) all mention specific bullets by brand in the load data. Bullet makers use their own bullets and powder makers often use known brands. Western Powder seems to list almost every bullet brand I have heard of and they market Ramshot and Accurate powders.

What they don't do is give dimensions of the chosen bullet, which would be even more helpful than naming the brand and size of bullet or even the seat depth. If your manuals don't list bullets with the load data it's time for newer manuals

Nosler load data goes as far as telling you how much volume is in the case in grains of water

Edited by TonyK
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Nosler load data goes as far as telling you how much volume is in the case in grains of water

What is grains of water? obviously its the weight of water for a certain volume. I have never heard of Noiser. BTW weight/volume=density or specific gravity. In my field we use the density of liquid chemicals relative to water to determine if its a floater or a sinker. I'm curious to learn how it is used in reloading

thx

Edited by Quag
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Specific gravity is irrelevant. http://www.nosler.com/9mm-luger-parabellum lists the actual EMPTY case volume in gr of water. They do also list load density of the powder, in percent volume of the case after the bullet has been seated, for each powder type and charge they have tested. Some of those powders don't fill the case and some are compressed. It was interesting to read that. You can look up the dimensions of different bullets and do the math, but if you seat a 115 and 124 gr bullet to the same COL (as an example: both RNs from same manufacturer), there is a .047 cubic inch change in case volume. Obviously using the same powder charge will increase or decrease pressure in the case. The same would apply to a RN vs. FN bullet of the same grain size. If the lengths are different, which they most likely are, seating them to the same COL will result in different pressures if the same powder charge is used because case volume, after the bullets are seated, will be different. So, the issue becomes: if you seated FN and RN the same COL, you may have a pressure problem. And if you aren't taking the different length of the bullets into account when setting you seating die, maybe your just lucky that something bad didn't happen. And I think that's why I originally started this thread. It's been a while and I can't remember.. lol.. My decision was to load all the FNs for my Glock and buy RNs to load for my XDm, as it just seems not to like any recipe I've used for it with a FN

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A buddy I shoot with has feed issues with his XD's as well, both an XDS and an XDM. His just don't like Xtreme FP's but they feed Xtreme RN's without a problem

Everyone seems to think this is mainly a 1911 problem but mine, an Remington R1 and a Springfield Mil Spec, will eat anything I have ever fed to them

Why they use water in grains is a very simple way to measure the volume inside an irregular shape. The old school way I heard of doing this yourself is to seat a bullet in an empty case with no primer. Weigh it on your scale. Use a syringe to fill the empty case through the primer flash hole and carefully weigh it again. The difference in the weight is how much water is in the case by weight.

It takes some additional steps and math but knowing the internal volume helps ballisticians come up with the loads you find in your manuals.

Edited by TonyK
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The volume displacement with water is interesting. Hadn't thought of it like that. Hope I didn't come off sounding like a jerk, TonyK. I've been accused of over thinking things.. Lol.. So be it. I don't think it's good to blindly follow the manuals and not have an understanding of how things work. Even more so when you start adjusting COLs to fit your gun. I'd hate to see someone make a mistake either from carelessness or lack of knowledge.

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Nosler load data goes as far as telling you how much volume is in the case in grains of water

What is grains of water? obviously its the weight of water for a certain volume. I have never heard of Noiser. BTW weight/volume=density or specific gravity. In my field we use the density of liquid chemicals relative to water to determine if its a floater or a sinker. I'm curious to learn how it is used in reloading

You typed "Noiser" but the post quoted is "Nosler" (with an L and not an I). You have never heard of Nosler?

http://www.nosler.com/

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  • 1 year later...

ok, sorry i hate to necro an old dead thread, but i am trying to search before posting the same thing over and over, and there is a ton of good info here BUT, i am new and still have a few questions:

Assuming that your gun will feed both RN and FN... or HP... or anything else... WHY would you chose one over another? Is one better than another accuracy wise/cleaner holes/etc? If your gun would feed any and you were able to purchace any why one over another.

And second, i'm sure it is here somewhere, but how does changing OAL effect accuracy.... i am just starting reloading .40 and so far i have been staying with the 1.125 stock length... assuming that a longer length would chamber properly i understand that it reduces the pressure, but how does that effect accuracy/recoil/anything else

I'm shooting my G35 in production right now so i am working on finding a good (for me) minor load. I am new to reloading and learning a ton. My last run of ammo that i will be trying this weekend is Berry's FP 180gr, 3.8gr WST, 1.125 OAL, .42 crimp, Federal Match primers. I have been trying to find a light recoiling accurate minor load, and tried playing with springs but honestly i didnt feel/see a difference with the 22# or the 13# or anything inbetween on the light loads, but i am used to shooting Gov Issued .40 on a stock service weapon, so anything is better, lol

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ok, sorry i hate to necro an old dead thread, but i am trying to search before posting the same thing over and over, and there is a ton of good info here BUT, i am new and still have a few questions:

Assuming that your gun will feed both RN and FN... or HP... or anything else... WHY would you chose one over another? Is one better than another accuracy wise/cleaner holes/etc? If your gun would feed any and you were able to purchace any why one over another.

And second, i'm sure it is here somewhere, but how does changing OAL effect accuracy.... i am just starting reloading .40 and so far i have been staying with the 1.125 stock length... assuming that a longer length would chamber properly i understand that it reduces the pressure, but how does that effect accuracy/recoil/anything else

I'm shooting my G35 in production right now so i am working on finding a good (for me) minor load. I am new to reloading and learning a ton. My last run of ammo that i will be trying this weekend is Berry's FP 180gr, 3.8gr WST, 1.125 OAL, .42 crimp, Federal Match primers. I have been trying to find a light recoiling accurate minor load, and tried playing with springs but honestly i didnt feel/see a difference with the 22# or the 13# or anything inbetween on the light loads, but i am used to shooting Gov Issued .40 on a stock service weapon, so anything is better, lol

The main reason for choosing FP or HP over RN is that the center of gravity is moved farther back when the pointy part of the RN is cut off (with the flat nose), and moved even farther back with the HP (even though neither the FP or HP have actual "points" :roflol: ) At least this is the reasoning that is generally promoted. I'd say try the different profiles and see what works better in your gun. RN are definitely cheaper and if you don't see an accuracy difference, why spend the extra money? JMO

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  • 5 years later...
On 12/22/2013 at 3:57 AM, Justsomeguy said:

A lot of 1911 types are not fond of flat nosed or even semi-wadcutter type bullets, but will feed round nose types just fine. It has to do with the feed ramp and angle plus the opening to the barrel which oftentimes requires some "gunsmithing" attention to get the flatter bullets to feed, and even then they may not be 100% in some guns. Doing the mods may make them feed better, but increases the area slightly that does not support the web of the cartridge by the feed ramp and may be more prone to some case expansion at that point in 1911 types.

 

All my 45acp 1911s love FPs, I started with the Hornady 230 FP back in 1981 and loaded them hot for a BPD buddy. Still do using the Nosler since Hornady dropped their FP. 

 

I am new to 9mm, and happened to get some Berry's just for practice (only bullets I could lay my hands on) and at my age, 9mm is easier on this old carcass. 

 

I'd like to use 231 because we have a ton of it for 45acp use. This has to work in my Springers and a friends stock Glock 19.

 

Any advise would be greatly appreciated and yes I know this is an old thread

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