Reloading FPS

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BRADRAMSHEAD95

Member
Hi guys need help

Im just getting into reloading, I’ve started reloading a few rounds in 243 I’m following the lee precision manual, I’m starting at max load and work down in small increments or starting from the middle and working up, but I’ve loaded the max and I’m not getting anywhere near the FPS it says I should be. Saying I should have 58gr bullet up to about 3700 and I’m getting 2700 need help please
 
That is what I do, I start lower I work I’m my way up, if I want to reach the max load. Obviously depends on the accuracy aswell. This was just a quick example but it happened I’ve if I would to the other end of the scale. I understand every gun is deferent but 1000 FPS is a lot
 
I think we were both responding to your statement that "I’m starting at max load and work down in small increments" which started the alarm bells ringing.

How are you measuring your velocity...is your Chronograph accurate? Can you check it against another one?

I don't load for .243 but you might give some details of the rifle, barrel length, twist etc. and the bullet and powder load for those that do to compare...they may be able to guide you more effectively...

If you don't have the starting load this passage from the Vihtavuori Website gives a method for starting and working towards the max load...



"The maximum charges must NEVER be exceeded. Start loading with the starting load according to the loading data. If there is no indication of the starting load, use a 15 % lower charge than the listed maximum. When loading cartridges for which the listed charge is 10 grains or less, after firing 10 rounds at the minimum weight (15 % below maximum), increase charge weights by 0.2 grains and fire another 10 rounds. Repeat this procedure, if necessary, until you reach, but do not exceed the maximum listed charge. The same process is followed for heavier charges except that charge weights from 11 to 25 grains use increments of 0.5 grains. For charges over 25 grains increments of 1.0 grains will be correct. If even a single test round shows signs of excessive pressure discontinue the use of the load. Do not fire even a single additional cartridge. Seek qualified help before proceeding! The traditional sign of overpressure is a flattened primer.

When flattened primers start to occur, it is a definite warning that the charge should be reduced, quickly. Brass getting into the ejector and extractor cavities is a worse case. Blown out primers are worse still. If a case ruptures it may be a sign of a defective case or a truly lethal chamber pressure.

In case of overpressure signs it is wiser to back off, to be safe rather than sorry. Why risk potentially fatal injury? Better to stop shooting and immediately discard all such reloads. Read also the Reloading Safety Rules on pages 16 and 17. There are numerous factors which can change the ballistic performance of a load even when the data is followed exactly.

For example: The internal dimensions of a firearm can vary greatly even between two of the same make and model. Pressures can vary to extremes as different firearms are used. Each change in brand and even within different lots of a specific brand component can cause notable ballistic changes. Too, changes in ambient temperature can also cause ballistic altering pressures. Not every bullet of a given diameter and weight will produce alike pressure. Changes in case brand can also effect ballistics.

Pressure
There are numerous other causes of varying pressure levels. Therefore it is essential that the reloader be well versed in the methods of carefully working up a reload powder charge in small increments as outlined in the various reloading handbooks that are available from reliable sources. The data on this website is not intended for use by persons not thoroughly versed in such procedures. These instructions should be supplemented by a good recognized reloading handbook that offers all appropriate information."
 
Start low (min) and work up (towards max) looking for over pressure signs.
It doesn't make sense that you are 1000fps adrift.

What is your choice of Bullet and Powder and what weight of powder ?
 
Last edited:
BRADRAMSHEAD95 said:
Hi guys need help

Im just getting into reloading, I’ve started reloading a few rounds in 243 I’m following the lee precision manual, I’m starting at max load and work down in small increments or starting from the middle and working up, but I’ve loaded the max and I’m not getting anywhere near the FPS it says I should be. Saying I should have 58gr bullet up to about 3700 and I’m getting 2700 need help please
Click to expand...
What powder? What barrel length? How deep are you seating the bullet?~Muir
 
Yep, 1000 FPS is a long way away from where you should be. In fact so far out that alarm bells are ringing to suggest you are doing something glaringly wrong.

Before we go any further we'd need to know what powder you are using, what weight of powder and how you are measuring it.
Then how you are measuring your muzzle velocity once you've loaded the round. What rifle? What barrel length?

With this data we'd be able to spot any obvious errors, then we can go onto how you are loading the rounds. If it helps, I'm not far away in the Western End of West Yorks, and I'd be happy to show you if you need a hands on demo.
 
Hmmmm ...... loading 58gr .243 bullets and they’re 1000 FPS adrift from the expected book velocity?

Maybe stop using those .308 cases and dies then? :coat:
 
Go carefully mate, not trying to lecture you at all but if you’re only doing that speed with 58 grain bullet then something is seriously wrong, are you sure you’re using the correct power? even the lowest book charges should see way more FPS than that.

Have good read of a manual like the hornady one, Nosler one is also good. And maybe even go onto eBay and buy a book called the ABC’s of handloading. Watch some videos on you tube too, there’s loads of geeky yanks with some good videos. Google a guy called Panhandle precision.

I’m honestly not trying to belittle you mate, but homeloading is potentially very dangerous if things are not done properly, Remember any gun going off, (shotgun or rifle) is several tons of pressure exploding centimetres away from your face!

It is a seriously enjoyable little hobby when you get the grips of it though, just go steady until you’re confident with what you’re doing

Matt
 
Scapegoat said:
Yep, 1000 FPS is a long way away from where you should be. In fact so far out that alarm bells are ringing to suggest you are doing something glaringly wrong.

Before we go any further we'd need to know what powder you are using, what weight of powder and how you are measuring it.
Then how you are measuring your muzzle velocity once you've loaded the round. What rifle? What barrel length?

With this data we'd be able to spot any obvious errors, then we can go onto how you are loading the rounds. If it helps, I'm not far away in the Western End of West Yorks, and I'd be happy to show you if you need a hands on demo.
Click to expand...
Hi mate thank you for the comment

So I’ve got browning x bolt
I’m using lee precision kit
I have the balance scales lee precision (not sure if I like these tbh)
Vihtavuori n140 powder

So I started loading at 39gr and work my way up to 43 gr
I’d make 5 of each working up 1gr at a time
I’d fire them get my groupings decided which was best found that 42gr work the best. So I went down and up half a gr loaded 5 at 41.5gr and 5 at 42.5 found that 42.5 was the Most accurate through my gun. Then I used my Caldwell ballist chrono and I can’t remember what I got of the top of my head but I was a lot less that what I thought it should be. So I just thought for peace of mind I’ll load 5 at max which is 43.2 so I loaded this 5 times and got 2740fps which is a 1000 less that what it should be at
 
Field chrono testing is not the same as lab testing ammunition and likely as not yield very different results.
Barrel length impacts, as does bullet seating.
You can at least expect to lose around 30 fps per inch if your barrel is shorter than the lab barrel data.
However 1000 fps difference would suggest a significant error either with your chrono, rifle or ammunition.
I’d likely suspect the chrono first, but double check the ammunition for sefety.
 
Matt. said:
Go carefully mate, not trying to lecture you at all but if you’re only doing that speed with 58 grain bullet then something is seriously wrong, are you sure you’re using the correct power? even the lowest book charges should see way more FPS than that.

Have good read of a manual like the hornady one, Nosler one is also good. And maybe even go onto eBay and buy a book called the ABC’s of handloading. Watch some videos on you tube too, there’s loads of geeky yanks with some good videos. Google a guy called Panhandle precision.

I’m honestly not trying to belittle you mate, but homeloading is potentially very dangerous if things are not done properly, Remember any gun going off, (shotgun or rifle) is several tons of pressure exploding centimetres away from your face!

It is a seriously enjoyable little hobby when you get the grips of it though, just go steady until you’re confident with what you’re doing

Matt
Click to expand...
Don’t think your belittling at all mate, I’ve not loaded since I got these readings. As it was a waist of time because something obviously wrong hence why I’ve posted on here. If you look at my last comment have you got any comments on my process
 
I’m away at the moment so I don’t have the book that I wrote it down in, but of the top of my head it read 2740 FPS 3 times and 2 miss reads
 
BRADRAMSHEAD95 said:
I’m away at the moment so I don’t have the book that I wrote it down in, but of the top of my head it read 2740 FPS 3 times and 2 miss reads
Click to expand...

When a chrono repeats a number several times like that, I assume a problem. Ammo is rarely that repeatable.
 
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