.303 British winning loads and tricks... ( here mine)

[bow]

Hi! I'm looking for a .303 winning load or loads.. My tricks:

- Sort any brass by brand , weight and rim tickness. Weight variation admitted: 0.5 grain.
Not use PRVI brass: i checked standard deviations usinga cronograph , PRVI brass produces higher standard deviation because has got a larger flash hole. If you have headspace problems , try another bolt head.

- Primer : .303 British brass has a conical shape , here works better federal premium instead bench rest primers.

- Bullet: i have only 4 and 5 grooves rifles, so Sierra hpbt 174 grainer works fine. But does something work better?


-Powder : i use N140. What you use?

Last thing: chamber are larger than modern civilian rifes. After 4 or 5 shots brass isn't symmetrical so i mark it with felt pen in a way i could chamber reeloaded ammonition at the same way each time i fire.

What can i do to get better results?

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[Patrick Chadwick]

-Powder : i use N140. What you use?

Definitely the No.1 choice around here.

---------- Post added at 09:22 AM ---------- Previous post was at 09:20 AM ----------

so Sierra hpbt 174 grainer works fine. But does something work better?

The 174 or 180 gn Spitzer types from Sierra/Speer may work better if the throat is a touch worn. Worth a try.

[Patrick Chadwick]

After 4 or 5 shots brass isn't symmetrical so i mark it with felt pen in a way i could chamber reeloaded ammonition at the same way each time i fire. What can i do to get better results?

Neck-size your cases. This not only reduces stress on the brass for a longer case life, but retains the fire-formed shoulder for better centering of the front end of the case. Nothing much you can do about the loose back end - except, of course, to maintain the orientation, as you are already doing.
Do not crimp the bullet at all.

On the first firing of a new case, you can use the fishing-line trick to keep the base back against the bolt face, and it may help to center the base as well (Jmoore et. al. please comment!). You can also use a neck expander to put just enough bell-mouthing on the mouth that the neck is also centered for the first firing, when the shoulder has not yet been formed to fit the chamber. Take a new, empty case and widen the mouth until it starts to rub in the chamber. Widen it a gnat's whisker more, so that you really have to close the bolt firmly. Remove the case, and the mouth will have a bright ring where it has been queezed down to fit the chamber. Measure that diameter and compare with the mouth of a loaded case, and you have a good idea of how much slop there is in the chamber neck. The first firing with the expanded neck reduces the one-sided expansion of the case that will otherwise occur. On subsequent firings, the now formed shoulder will help to center the case provided that you use neck sizing and not full sizing.

[jmoore]

I only neck size about 2/3 to 3/4 of the neck. Other than that, I think it's well covered above.

Have used IMR 4064 for ages. VV powders are exspensive in the US. Probably not available for the most part right now, anyway. (Nor is 4064 for that matter, but I've enough to do a while.) Have tried some other powders, but keep returning to 4064. That and Sierra 180 gr PSP bullets. Usually I can't see any improvement with the 174gr match bullets.

[Patrick Chadwick]

I only neck size about 2/3 to 3/4 of the neck.

I leave about 1-2mm on mine. A pragmatic amount arrived at by setting the sizing die so that it just about "kisses" the shoulder. It is probably the un-resized portion of the neck that provides the centering for the reloaded cartridge, rather than the shoulder.

---------- Post added at 01:23 PM ---------- Previous post was at 01:19 PM ----------

Usually I can't see any improvement with the 174gr match bullets.

The advantages of the low BC of an HPBT vs a spire point/spitzer will just not show up below 300 meters- - take a look at the Sierra trajectory tables. I find it instructive to study what the benchresters do, and think through "why".

[bow]

Many thanks Patrick and jmoore. Only some questions lasting:

fishing-line trick

I red about O-ring trick in the past, but...how to fix the fishing line to the brass'rim?

You can also use a neck expander to put just enough bell-mouthing on the mouth that the neck is also centered for the first firing, when the shoulder has not yet been formed to fit the chamber

What is a neck expander? i've never seen one of them.


Last thing: i do resize my brass using Lee collet die, it works fine but it resizes the Whole collet, So , in order to resize a part of the collet only, i should use a RCBS collet die or a full length dies unscrewed the exact amount of turns. Right?

[WarPig1976]

You can use a small rubber washer,available at plumbing supply stores instead of fishing line, holds itself on.

[Patrick Chadwick]

I red about O-ring trick in the past, but...how to fix the fishing line to the brass'rim?

Here's the link to the comprehensive article by Parashooter:

https://www.milsurps.com/content.php...101-for-.303-s

It seems that the monofilament fishing line will hold the curl long enough to chamber the cartridge.

[Patrick Chadwick]

What is a neck expander? i've never seen one of them

Here are some photos:

http://de.images.search.yahoo.com/se...=neck+expander
or
http://www.trackofthewolf.com/catego...-EXPANDER-PLUG

3-die sets for parallel-sided cases, such as 45-70 and a lot of pistol cases (38 special etc) contain
1) a sizer die
2) the expander die
3) the seater die

For bottleneck cartridges, where dies normally come in 2-die sets, separate expander dies are also available. One expander, for .30/.308 for example, can often be used for several different chamberings (30-06, 308, 30M1 Carbine etc). Lee makes a universal expander, but the taper is very steep and it therefore requires careful setting up to avoid producing a mouth that looks like a trumpet.

[Patrick Chadwick]

If you need components that you cannot obtain locally, I suggest that you contact Matteo

https://www.milsurps.com/member.php?u=23736

and his friends at traxarms in Florence.