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Flat point vs round point


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I switched from 124 gr plated round points (X-treme) to 124 gr flat points, due to availability / sale price. The flat points are considerably shorter, .059", so by keeping the oal the same, it will create more case volume. More case volume equals less pressure and possible squib or cycling problems. By shortening oal to keep the same case volume and pressure, I'm making the oal pretty short and have some concerns with possible feeding issues. Hogdon has no load data for flat points. Any suggestions on where to start? Just start over with new test loads, keeping same oal with more powder? (currently using 4.2 gr titegroup with rn)

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Hornady's 7th Edition manual lists 1.05" OAL for their 124 grain FP. I got a thousand of these on sale a few years ago and loaded them at this length and they ran fine in my M&P9, CZ-75Bs and Beretta 92 Brigadier. Your bullets may have a different nose profile, but should run fine at a shorter-than-RN OAL.

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Don't over think this.

I agree to an extent. Most flat points have a longer shoulder which will not let you load them as long as a round nose bullet. That longer shoulder will contact the rifling and cause a whole lot of problems, some of which can be dangerous. flat points need to be loaded shorter. It's just like any other load. You have to start low and work your way up.

First things first though. Make a dummy and keep seating the bullet further and further until it drops in and out of your guns chamber with no resistance one way or the other. Once you get to that point then start looking up similar bullet types in manuals and recipes close to your oal.

I switched from RN's to FP's once and loaded several hundred rounds that would not drop in my chamber. Nobody gave me the advice I just gave you.

Other than that, don't over think it

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Just to provide one more data point, when I loaded 125 gr Sierra bullets (with a more common rounded profile) they ran great at 1.12. When I got some of the Montana Gold hollow points (with the more truncated cone profile) I had to drop the OAL down to 1.10 for them to run in two of my guns and 1.09 was needed for the EAA Witness. Never have had to load as short as 1.05 though at one point I did run some at 1.06 and they did run fine.

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Actually I set up my press today and tested a couple different lengths in my two 9mm barrels (no powder or primer) doing the drop and spin test, and in think I'm settling on 1.080-1.083. The bullets are conical nosed. I'll make 4 or 5 test powder charges and test them hopefully tomorrow.

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  • 1 month later...

I have been using 147gr flat nose lead moly in my HS2000 (XD) for a long time with no issues. I also use 180gr flat nose lead moly in my 40 cal XDm's with no issues.

I just got a RIA 1911 Tactical 2 in 9mm and no matter what I do the flat nose will not run at all. I just traded what was left of them to another member on here for 135gr round nose lead moly. Round nose ran fine in the 1911 but the flat nose not at all. Some guns just seem to prefer different syles of bullets. If you want coated, Xtreme seem to be a good price right now. http://www.tjconevera.com/xtremebullets.html I have not bought from them but the price seems pretty good.

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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.

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  • 2 weeks later...

I have been loading with Berry's 147 grn RN FMJ OAL 1.14. They fed fine. Got the PF I wanted.

I am switching to MG FN CMJ (gift certificate can't beat free). I have heard of feed problems with FN. I loading up some dummy rounds and they seem fine. I did not change the die which gave me 1.14 on the RN. The FN OALs using the same die setting as for the RN came out at 1.10 OAL with the flat nose. Does this sound right? There is not a lot of FN data out there in the manuals. Can you consider at FN to have the same profile as a HP?

thx

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Another thought I measured the bullet length for the RN .674", and the FN or FP is .635. The OAL at the same die seating for RN is 1.14 and the OAL for the FN is 1.10. Subtracting the bullet lenght from the its OAL gives the lenght of the bullet in the cartridge; .465 for the FN and .466 for the RN. Given error these are the same.

As long as the bullet feeds right in the chamber and length of the bullet in the chamber is the same what happens in the chamber given the same load should be the same because the space for the gases explode in are the same even though each bullet's OAL is different.

So I guess I should stick with the 1.10 OAL for my 147 and chrono that. Does that sound right?

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This is exactly why I get ticked at the load manuals when they do not include actual length of just the bullet. Provided the loaded cartridge will feed, chamber and cycle in your gun it doesn't care how long or short it is.

The important thing is just how big the volume is inside the loaded case. And as you know this is determined by the OAL and the length of the bullet itself, so to use the data from a RN you need the length of just the bullet

So provided you are using the same bullet material (lead, plated or fmj) loading a FP (yes some makers do call them flat points) to an OAL that is less than RN data by the amount of the difference in length of the bullet is perfectly OK. But you have to know the exact length of the RN and do the math first. But I have run rounds across the chrono and the FP's loaded this way duplicated the data I got from the RN's as the case volume for the powder was exactly the same.

And you need to realize not all FP's are created equal. Some like Xtreme's for my 45 have very short tapered front sections while some Hornadys I have are much longer in the tapered section of the bullet. What OAL works for one will not work for the other. When loaded longer the Xtreme's jam the shoulders into the rifling so I have to load them very short. I didn't include any numbers since I only load for my 45....

Best thing you could do is load up a bunch of dummy rounds and cycle them by hand. If you can run them through your gun by hand you shouldn't have an issue. If not, back to the drawing board.

Using HP data might work if the HP has the same profile and the same length bullet. My Xtreme FP's have straight front sections while most HP's are rounded with the front cut off when looked at from the side. And that rounded side really makes a difference in how a round chambers in most guns. So the OAL for an HP might not work for your FP's.

And like was mentioned before start light and work up. Preferably over a chrono.

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That's exactly the problem I had with Xtreme FNs. Data says COL should be one thing. They hit the rifling in my XDm so I shortened them to 1.084 after also decreasing powder charge some. Accuracy, for whatever reason, just wasn't acceptable to me. I ended up loading them all with 4.0 titegroup and shoot them through my glock, which loves them. Gone back to round nose for the XDm and trying 124 gr plated from Rocky mountain reloading. They are loaded to jacketed velocity.

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I have loaded about 20 rds of FP/FN 147 MG at 1.10 OAL (1.14 OAL in RN). Hopefully I can get to the range when this snowstorm ends to try them out. I loaded 5 dummy rounds and cycled them about 3 times. I had a couple of misfeeds but I attribute that to how I was racking the slide. I figure I have about .02 to .03 inches to lengthen the rounds if they don't feed right.

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Remember that they also need to fit in the magazine. I was trying to load some 180gr .40 long for my XDm so that the bullet was almost touching the lands and grooves. When I got to the length that was perfect, they were not even close to fitting in the magazine. I then had to change the seating depth to fit the mags and then tune it if needed for accuracy from there.

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