Need Help With .300 WM Loads (No Accuracy) (Bolt Hard To Close)

[ExpiredMember2019]

Here's the situation: I have a Remington 700 SPS stainless .300 Win Mag that has been re-mounted in an HS Precision stock. It has been bedded and recrowned by a reputable gunsmith. I have some formal training in precision rifle work and have applied a lot of this to my hunting. Last year, I got this rifle a little late and had pure hell trying to find a factory load that would shoot with even a modicum of precision. After a lot of expense, I finally settled on Remington Premier with the 180 grain Swift Scirocco. It wasn't great but it worked fair out to 400 yards.

Elk hunting season comes and goes....I get the rifle recrowned and professionally bedded....

This year, I wanted to work up a load and a friend of mine ("Trigger Time" on Sniper's Hide) helped me out with that. I bought some once-fired brass from a guy on Sniper's Hide and some Swift Scirocco II 180 grainers from Midway USA...we load them up with various amounts of Reloader 22. We did not measure OAL of the brass. My buddy seats the bullets just off the lands.

Today, I went to the range and test fired the rifle and had two troubling observations:
1) The bolt was very hard to close on all of the cartridges (One would not chamber)
2) The most accurate load was 3" at 100 yards. The others were approx 4" to 6". (The rifle was shooting better than this with factory ammo before it was recrowned and bedded.)

Now I am really worried about lots of things:
- Is the brass too long?
- Are the bullets seated too shallow?
- Is this rifle a lemon?
- Is the Scirocco just not going to work?
- etc..

I miked the factory rounds versus our loaded rounds. Here's the factory loading:

Here's my loads:

Here's a side by side comparison of 3 factory loads and 3 of my loads. Do you see anything wrong with the cases? I thought at first that the shoulders might have been higher on my brass compared to the factory brass but I think I was just being paranoid.

While I may have some formal training in precision shooting, I have NONE in reloading. I admit my ignorance and ask for your help. If the bolt is hard to close, doesn't that mean that either the brass is too long or the bullet is seated too long? Couldn't this be affecting accuracy?

Any thoughts? I really need some help here. I'm supposed to leave for Colorado in about 2 weeks. If this rifle doesn't work, I'm going to end up hunting in the mountains with a heavy AICS Remington 700 in .308 and that won't be cool.

I'm supposed to go back to my buddy's house tomorrow to try some Nosler Accubonds and maybe a different seating depth on these Sciroccos.

I will gladly accept any and all advice.

Doug

 

[Nomad]

Take a fired case put in your die and and start screwing down your
die 1/8th turn then try in your rifle see if its hard repeat until the bolt
closes easy with just a little resistance.
Now place a bullet in a "UNprimed" case that works smooth in your rifle
measure the length about 40thousands over size now take a candle and
put the smoke on the bullet end and see how it fits if too long rifling
marks will be on the bullet turn down the bullet until marks are gone should
be 3 to 7 thousands off the riflings generally works at this point.
A load that works very well for a 300 Win with a 200 sgk is 76.5 RL-25
215M primers in Win cases.
Good luck on your hunt..

 

[kraky2]

Nomad most likely (I'd say about 95% sure has it right). Bottom line is NEVER get brass from someone else unless you are pretty sure about your reloading and it will really help if you have a headspace gauge kit. Last thing is make sure that you are not binding above the belt. If the gun that shot the brass had a generous chamber the bulge above the belt could be a problem. Make sure if you measure just above the belt you are .512 or under. No belted FL sizer goes all the way to the belt because they are afraid someone could move it back and make a headspace problem.
If you are gong to buy brass somewhere else spend about $22 for a redding body die.....you can actually resize brass that has been reloaded to factory dimensions.

 

[Rimfire]

Doug

Without seeing it I would start with one thing at a time. Take a few pieces of the brass you bought and chamber them with out a bullet seated. If they are still hard to close you know its the brass (my guess) If they are also hard to extract chances are the body of the case forward of the belt has grown. If they easy to extract and hard to close it's head space and I would then follow what Nomad said.

 

[Ridge Runner]

here's what I do to get started
die set up
take a case and trim to length, then run an expander ball 1 size bigger into the case mouth (in your case you could just use a 338 win mag case) now resize a lil at a time till you can feel the slightest resistance when the bolt closes and lock the die down there. your die is set for your chamber.
COL
take 2 orings that fit snug on your cleaning rod, and a fairly long 6/32 screw with the head cut off smooth.
screw the screw into your ramrod till it bottoms out (finger tight)
put one oring on your ramrod and slide it up to the handle.
make sure the bolt is cocked and slide the rod down the barrel till it contacts the bolt face. slide the oring down till it touches the muzzle.
remove rod and bolt from rifle.
put 2nd oring on the rod just below the first, insert a bullet into the chamber and use a pencil (erasor end first) to gently push the bullet up against the lands.
reinsert rod slowly until you feel it contact the bullet tip, then slide the 2nd oring against the muzzle. remove rod and measure muzzle side to muzzle side the distance between the orings, this is your max COL for your rifle with that bullet, now start working up a load.
RR

 

[NYLES]

Easier way for max COL

take a preped brass

cross cut the neck with a dermel for four slots

FL resize it

put in press until bullet starts to seat.....stop

camber in rifle seating the bullet as you the close bolt

once bolt is closed eject round ......thats as long as they can be

if hard to chamber add a cross cut to minimize neck tension you just want it tight enough to hold the bullet in the case as you close bolt ....too much force and you can stick bullet in barrel.....be easy!

I have a full article on this just cant post it up

 

[britz]

First off I would purchase new win, nosler, or lapua brass, prep them as well as you can. trimm them to lenght, sort within 1 grain in weight deber primer pocket, true the primer pocket and keep all brass in a lot with the same amount of firings on them.

Swift Scicciro's are not known for exceptional accuracy. They are a good bonded bullet, but I personally didn't have good luck w/ them in any of my rifles. I've had better luck w/ accubonds.
I noticed that your loads had a substantial difference in length from one to the next 3.602 3.568. I will assume that these two loads were from sepperate lots. If not, then your lengths are verying way way too much and you should measure from the ogive rather than the tip since the tip will vary from bullet to bullet. When trying to find a good load only change one variable at a time. Most, but not all rifles like bullets seated close to the rifleing. Wby for example has lots of freebore. You will experience pressure build up when you get close to the rifleing.

IMO the easiest way to find a COL for a particular bullet is to take a fired case and slightly deform the neck. Use a black marker to paint the bullet and just barely push it into the case. Chamber it and unchamber it and knock the bullet out w/ a cleaning rod. The case will have left scratch marks on the bullet for you to load to.

 

[ExpiredMember2019]

Success!!

Well...the problem has been solved!

It appears that the problem was threefold: 1) Bad brass, 2) A finicky rifle, 3)Seating depth (possibly)

My buddy loaded a whole bunch of different loads and bullet/case/powder combinations to see what would work. I also bought 100 pieces of new Winchester brass and gave up on the inconsistent and problem ridden "once fired" brass I bought from someone else on Sniper's Hide. (No names will be mentioned here...)

After a lot of work, we found that the following load(s) consistenly shot 1/2" or 3/4" at 100 yards:

- 180 grain Nosler Ballistic Tip and 75 grains of Hodgon H4831SC
- 180 grain Sierra Match Kings and 75 grains of Hodgon H4831SC
(We seated the bullets slightly deeper than the first loads pictured above.)

These were tested with success in my new Winchester brass. For whatever reason, my rifle hates Swift Sciroccos, Nosler Accubonds, Ballistic Silver Tips, and Alliant Reloder 22 powder. Go figure.

We're going to load up 100 rounds of the Ballistic Tips, check the load with the chronograph, and then confirm the Exbal drop tables. After that, I'll practice on steel at various ranges from the major positions.

I sincerely appreciate all of the replies, private messages, and emails that were offered. Your input has been invaluable.

Some lessons learned on my part:

1) Don't ever buy second hand brass again, no matter what.
2) Don't give up on your rifle until you have tried plenty of combos; even if the popular loads/bullets don't work, that doesn't mean that another one won't
3) Don't get hung up on trying to force a particular bullet to work for you. Just because it's supposed to the be a bad-*** super bullet doesn't mean it will shoot worth a **** for YOU. Be open to trying something else.
4) Prep brass
5) Study more about reloading and case development

Words cannot describe the relief that I feel in knowing that my rifle is not a lemon and that I now have a load that has been repeatedly proven to be accurate out of this rifle. No elk within range will be safe now!

Doug

 

[Huntinfool]

Welll!!!

At first glance it appears you may have the bullets seated too shallow! What method did you use to come up with your seating depth?

This would be the easy fix if that's the main problem the others have given you good advice. I use a stoney point overall length gage to determine where my are seated to!

Good Luck,

Chuck

 

[Innovative]

DougD,

You have two separate problems:

(1) Your bolt should close on a loaded chamber without using ANY force. The problem is not likely to be excessive case length, I'll bet it's excessive case WIDTH. This is a very common problem when handloading belted magnum calibers. Read the post above (about the 300 Weatherby). He also has a belted caliber with a case width problem.

(2) The accuracy problem is another issue. I'd solve the chambering problem first, then try different bullets. Some shooters get stuck on trying one bullet for way too long. Some exceptionally fine rifles just perform better with a particular bullet. By the way, some of your bullets are seated way too deep, while others appear way too long. What's with that? On hunting rifles, I usually start by seating my bullets to the maximum length that the magazine will allow. I also measure handload length from the bullet ogive back. This shows accurately how far you are off the rifling. Read my website for tech tips that will solve both of these problems and others.

- Innovative

 

[mddietz]

DougD

After you shoot this new brass and then reload it...... And you have the same problem as mentioned before...Look me up, I think I will have the answer.

 

[just country]

300wm have a short neck. take a new case, resize with hornandy 30cal. neck sizer. resize all cases new and used with the hornandy neck sizing die. i do not full length resize my cases. i reload them 3 times and throw the cases away. i keep track of cases and the reloads in a book. the neck sizing dies come single. I have 7 in different neck sizes. from 22,24,25,26,284,30and 338. they r great and fast. i use berger 168gr. vld and 180gr. vld bullets. i use 4831sc for both loads. 168gr. i use 78.5grs and the 180gr. i use 77grs. of powder. 215 primers winchester brass. my rifle is a 700 left hand la with a 29 in rock river arsenal barrel. #6 contour. i seat my bullets touching the lands and grooves. i shot the same brand of bullet and the bullet seater is set to this brand of bullet. Practice practice practice. u will get better, shoot shoot shoot. LB Schertz TX.

 

[Dr. Vette]

LB Schertz TX.

Larry,

Do you realize that you are digging up threads and answering questions that are 5 and (in this case) 7 years old?