Faster powder, short barrels and sound mods

Selous

Well-Known Member
I have recently had my 308 chopped from 24 inches to 20 and threaded for a mod. I have always used n140 for my hand loads but recently have been wondering if it may be better to use a faster powder like H4895 to get a more complete burn in a shorter tube . Has anyone tried this approach before, also will there be any reduction or change in sound when moving to the faster powder
 
Yes you can turn towards a faster powder, but with that comes two adverse effects, recoil and pressure.
I would ask someone to run Quickload for you with your load and see what the powder burn is.
I would run mine but it seems to have caught a cold.

regards
G
 
I think the barrel on my Blaser is around 21 inches, so a little longer than yours. I use RL15 and with Hornady Spire Points and a book load I get 3000fps which is good for a 308 in my view. It gives a little more recoil than my light load, as the physics would dictate, but I've never noticed any significant difference in the sound.
 
I think the barrel on my Blaser is around 21 inches, so a little longer than yours. I use RL15 and with Hornady Spire Points and a book load I get 3000fps which is good for a 308 in my view. It gives a little more recoil than my light load, as the physics would dictate, but I've never noticed any significant difference in the sound.

Thanks for the help chaps

That is fairly hurtling for a 308, I thought I was doing ok with a 150 grainer at 2900 GPS from the 24 inch tube. Is it a 150 that you are using or a lighter bullet. To be honest I am less likely to be chasing velocity as the 308 is a woodland only rifle for me so its no great problem if I lose 100-200 fps so hopefully pressure and recoil will not be an issue.
 
I think the barrel on my Blaser is around 21 inches, so a little longer than yours. I use RL15 and with Hornady Spire Points and a book load I get 3000fps which is good for a 308 in my view. It gives a little more recoil than my light load, as the physics would dictate, but I've never noticed any significant difference in the sound.

What weight of bullet caorach? i'm very interested to learn how you achieved that kind of velocity mate.

Ian.
 
It is a 150 grain bullet - I wasn't chasing velocity but just worked up to the most accurate book load. I was using the load for a long time before I shot it over a chrono and couldn't believe how fast it was. In terms of pressure all I can say is that some cases have probably had more than 10 firings with that load on them and the primers are firm to seat with no signs of pressure problems, just the normal wear and tear stuff.

Since that I've been playing with 150 grain Nosler Partitions and have found that they sometimes put chest shot sika straight down, which the Spire Points never did, so I've migrated to the Partitions as my main deer load. There is a lot less powder behind them and they are giving me around 2700fps but aren't as accurate as the Spire Points are so maybe I could do with some more work on the load.
 
Stick with Vit 140


My 20 inch AX loves it and the flash at the end of the barrel assists in follow ups for target acquisition :D
 
Stick with Vit 140


My 20 inch AX loves it and the flash at the end of the barrel assists in follow ups for target acquisition :D


I had the same when using H4895 in my 22inch Howa with Nosler 150grn partition.
I changed to N133 and the flame thrower stopped.

I have also tried N130 with Sierra 2120, and get sub MOA grouping with less powder.
 
What weight of bullet caorach? i'm very interested to learn how you achieved that kind of velocity mate.
.

I'd love to be able to tell you it was down to my skill but the truth was it just worked out that way. I'm relatively new to reloading and really only want a load for deer and to pop at a few targets. I started slowly and messed about with some very light loads for plinking. Then I decided on the Hornady Spire Points (150 grain flat based ones, I think the part number is 3131) for my deer load. Getting a reliable supply of powder is tricky but I managed to get some RL15 and so started working up with it. I got an accurate load which I used a lot on targets etc. but was concerned that it might be a bit slow. When I shot it over a chrono it was around 2500fps so I worked up. At book max I got another accurate load which I used for a year or more before I fired it over a chrono to discover it was making 3000fps.

It is possible the chrono is wrong though it has given reasonable figures for other loads I have shot over it. If you take a look at the Alliant page for RL15 you will find they quote 2919 for a 22 inch barrel so my figures are in the ballpark:

Alliant Powder - Reloader's Guide

For what it is worth I'm using CCI primers and Lapua brass. The brass doesn't quite have the capacity for the full "book max" load until it is once fired in my rifle, I'm sure you could make it fit by compressing it but I prefer to run the brass through once with a light load before using it with my full power loads.

I get no pressure signs at all and most of the brass has been loaded at least 10 times, some maybe a lot more, so it isn't killing the brass.

As stated I've sort of moved to a load using Nosler Partitions. Even though they are going a lot slower they seem to put sika down better for me. When I changed to the Partitions I did, initially, just stick them on top of the book max load that worked for the Spire Points but my view at the time was that it wasn't an accurate load, though the amount of testing I did was actually statistically insignificant. As my Partition load isn't as accurate as the Spire Point one I might see if I can do some more work and get it to group a bit better but, as I keep saying, my results are likely to lack any statistical significance and so are probably only a sop for my confidence.
 
Stick with Vit 140


My 20 inch AX loves it and the flash at the end of the barrel assists in follow ups for target acquisition :D

Have a tub of H4895 so will give it a go, probably wont make much difference but you never know!! My mum always said flashing was for bad men!!:eek:
 
I use RL10X which I use in an 18" barrel which was a deliberate choice of powder to help counter the loss of velocity. As per your needs, this rifle is used at mainly > 150m so I'm not obsessed with velocity and accuracy is good with swift scirocco II 150gr. Scierra pro hunter 150gr and RL15 also work well.
 
Back
Top