300 BO Chambering issue

[Rich22]

So I am FINALLY getting around to load testing the NOE 247s in my 16 inch 300 BO. I am however having chambering issues with the dummy round I made up. It is significantly marking the bullet (Hi Tek Coated). I loaded this fairly short for the bullet and don't want to really go much shorter if it can be helped. I know it has worked in other guns on a longer OAL. I worked very hard on trying to perfect these bullets and the process for them so if I cannot use them I am going to be real disappointed. My first test with cast, the NOE 311-155 did not work at all due to the nose size, this seems better at least. Apologize for the horrible pictures161853161854

Info

Bullet type 247gr NOE 311-247
Sized .309
Coating 3 Coats Hi Tek
Nose Diameter.2295
C.O.A.L 2.10

It did chamber and it ejected without issue. The OAL did not change from before to after. It is not totally fitting in my Sheridan case gauge but is VERY close. I am thinking I may be overdoing the crimp and once I can find my bullet puller I will check it. I am going to the range on friday so I am trying to get this done asap, if it wasn't for 300 other projects I would have started this before today. Any help would be greatly appreciated.

[jmorris]

The crimp does look over done especially on the 2nd photo. The mark in the coating doesn't look like a land issue, rather hitting something(s) on its way. Damage at that point won't lead your barrel though.

[BK7saum]

I have loaded the NOE 311247 in a whisper bolt action. The nose is a bore rider and is meant to extend into the bore past the throat. Your coating has likely led to a larger diameter parallel nose section that is causing your chambering issues. The nose (parallel section) in front of the drive band should be right around 0.300" for it to chamber correctly.

[BK7saum]

Noe makes a nose sizer to size the noses to a usable diameter if dropped too large from the mold or in this case after coating. I'm not a powder or epoxy coater, though

[jmorris]

I dont one think he is having issues with chambering.


It did chamber and it ejected without issue.

Just having concerns about the marks in the coating getting them there.

[BK7saum]

The second line of the OP said that he did have chambering issues.

" I am however having chambering issues with the dummy round I made up"

They look to be seat rather deeply with the crimp groove in the case neck. The apparent ring or marks on the ogive are indicative of a too"fat" nose section. I was just wondering why they were seated so deeply. It was my opinion that the deep seating might have been done to get around the thick powder coating on the nose.

Maybe they are seated and crimped to the specifies depth but I can't tell because of the coating. (Nope, he stated that they were seated deeply, also)

Brad

[jmorris]

The sentence after that is what lead me to believe the marks were his only issue, after the last line I quoted. Maybe he can clear it up when he gets back.


I am however having chambering issues with the dummy round I made up. It is significantly marking the bullet (Hi Tek Coated).

[Rich22]

The crimp does look over done especially on the 2nd photo. The mark in the coating doesn't look like a land issue, rather hitting something(s) on its way. Damage at that point won't lead your barrel though.

Yeah, I will readily admit I totally blew the crimp on this one since it was the first try, I will get it ironed out. I have no idea what it would hit in order to cause it.


I have loaded the NOE 311247 in a whisper bolt action. The nose is a bore rider and is meant to extend into the bore past the throat. Your coating has likely led to a larger diameter parallel nose section that is causing your chambering issues. The nose (parallel section) in front of the drive band should be right around 0.300" for it to chamber correctly.

I measured that area that I believe to be right in front of the drive band where it goes to (now) .309 and it measures .300.


Noe makes a nose sizer to size the noses to a usable diameter if dropped too large from the mold or in this case after coating. I'm not a powder or epoxy coater, though

Not to sound lazy but I would change molds before I would "double" size for both driving area and nose with the amount I am going to need. Even though I do already have the NOE .300 nose piece since I was doing an order and thought I may eventually play with it.


I dont one think he is having issues with chambering.
Just having concerns about the marks in the coating getting them there.

Correct, I do not see an actual chambering issue it seems to be going in without a problem. I will need to load up a bunch and see how it cycles and loads after firing.


The second line of the OP said that he did have chambering issues.

" I am however having chambering issues with the dummy round I made up"

They look to be seat rather deeply with the crimp groove in the case neck. The apparent ring or marks on the ogive are indicative of a too"fat" nose section. I was just wondering why they were seated so deeply. It was my opinion that the deep seating might have been done to get around the thick powder coating on the nose.

Maybe they are seated and crimped to the specifies depth but I can't tell because of the coating. (Nope, he stated that they were seated deeply, also)

Brad

I misspoke, my fault, I meant by chambering issue that the coating is getting damaged during chambering. I did seat them deeply to make sure it would fit in the mags, not have an issue with the nose due to the wide meplat. Measuring an uncoated bullet to the coated, the coating took it from .2985 to .2995. The deep seating was just done as a starting point.

I will pull the upper off and check the barrel and make sure nothing is messed up in there.

Thank you guys

[BK7saum]

Your welcome. Hope you get it figured out.

[jmorris]

I have no idea what it would hit in order to cause it.



Thats why I suggested marking a case with a sharpie on the top side so you could get an idea about where the damage is taking place. Might also clean your rifle/mag and look to signs of the coating where it hit. Inside the from lip on the mag and the feed ramps would be a good place to start.

[Rich22]

Thats why I suggested marking a case with a sharpie on the top side so you could get an idea about where the damage is taking place. Might also clean your rifle/mag and look to signs of the coating where it hit. Inside the from lip on the mag and the feed ramps would be a good place to start.

I totally did not see that, will do that and check.

[popper]

2 problems, 3 if you use the FCD. 1st - left pic is getting damage while going into the chamber. Hits the throat edge and nicks it. That will cause problems with shaved lead in the throat/neck area. Right pic is nose too large and really getting scraped by the edge. You have the nose sizer so do it on loaded if possible and definitely the coated ones. You only ned to nose size enough to keep the drive band from hitting. I can't tell if the seating die is enlarging the nose - it can with soft alloy. Get the high temp paint to coat the nose section of the mould or a new mould that has a 'good' fit nose. If you use the FCD - don't lock it down tight in the press. It pushes up on the case when crimping and WILL buckle necks - and they won't chamber. Don't ask - pulling 60 rounds today. The mould I use has a 0.297 dia., coated I still have problems once in a while - drive band goes in 0.1" and scuffs or scrapes - sometimes.

[dilly]

I have issues like this all the time. In fact, it happens so much that I'm beginning to wonder what I'm missing that everyone else is doing or not doing.

[Rich22]

Opened up the rifle, no obvious cause of the damage. Cleaned chamber and surroundings. Put together new round, OAL 2.102. Lightened up on the crimp, round easily gauges in my sheridan gauge. Chambered round and ejected. Same issue generally. Case was marked at 12 , 3 and 9 oclock positions. 12 being on top 9 left side and 3 right side. marks still there and generally same as before. Bullet has same dimensions as before.161925161926161927

[Rich22]

2 problems, 3 if you use the FCD. 1st - left pic is getting damage while going into the chamber. Hits the throat edge and nicks it. That will cause problems with shaved lead in the throat/neck area. Right pic is nose too large and really getting scraped by the edge. You have the nose sizer so do it on loaded if possible and definitely the coated ones. You only ned to nose size enough to keep the drive band from hitting. I can't tell if the seating die is enlarging the nose - it can with soft alloy. Get the high temp paint to coat the nose section of the mould or a new mould that has a 'good' fit nose. If you use the FCD - don't lock it down tight in the press. It pushes up on the case when crimping and WILL buckle necks - and they won't chamber. Don't ask - pulling 60 rounds today. The mould I use has a 0.297 dia., coated I still have problems once in a while - drive band goes in 0.1" and scuffs or scrapes - sometimes.

FCD was the only thing I could find that would reliably remove the expansion on a 300aac case, at least a year or so ago when I bought the dies. I am not tightening down and am going very light on the crimp, the new one at least. Nose sizing may work for testing but just not an option for the volume I am going to want to do so not much point. Also, I am not measuring anything greater than .300 anywhere before it goes into drive bands. I do not believe the seating die is enlarging the nose, the lead is medium in hardness and due to the flare on the case I am using very little pressure to get the bullet into the case. I have seen numerous people use this bullet without issues but it seems anything that is not jacketed is problematic in this rifle. At this point if the problem cannot be solved I am not sure whether to get rid of the mold or the upper. This would be mold #2 that this rifle cannot run.

[Springfield]

So how do they shoot?

[MT Chambers]

My my, FCD is the only thing to remove flare? For best accuracy leave the flare, it will help centre the bullet in the rifling. Try the bullet bare esp. if it's supposed to be a bore rider, I wouldn't worry if the gc is below the neck junction......lotta misinformation when talking about this round.

[leadman]

Take a look in your chamber and see if the is a leade on the rifling side of the throat. I am running into the no leade problem more frequently now with the newer guns.
Also try seating just a bit deeper to prevent the nose from hitting. With a semiauto you really want the boolit shy of the rifling. Especially when shooting cast as the ogive (radius of nose) can vary a little.

[Rich22]

So how do they shoot?

Shot approx 15 of these today. For the sake of this I am a horrendous rifle shooter. I have almost no experience shooting them. With that out of the way, these suckers shot great from an accuracy point of view. I kept a half dozen in the size of an index card at a little over 25 meters. My guess is the issue is skills, not the ammo. Bad part, did not function the gun whatsoever, I got not a single extraction. This was with 9.5gr of IMR 4227. My gun was never really put together with subs in mind. Its a 16 inch barrel carbine gas but I would really like to find a load I can use and train with some of these since I need so much work on my skills.

[Fishman]

You are not alone on the chambering problem. I have it too, same deal. Another forum I participate in yielded the suggestion of renting a throating reamer and carefully opening up the throat of the rifle to provide clearance.

[popper]

OK, cycle a dummy REAL slow and watch the ejection port. Watch for a 3 point bind when chambering. Nose hits edge of chamber. Solution for this is grinding the front edge of the mag lip til the bind goes away (rnd has to pop up to get pushed into the chamber - have to watch it as subs are heavy and nose dive can happen - jams then). You are trying to push a 2' long straight wall boolit into the hole. Chamber some dummys and then check for bent boolits by rolling on a flat surface. I run 1.95" COAL in my supers, short for the mag but just barely miss binding. Barrel maker was sent dummy rnds and he throated it right - ~0.2" - much shorter than most as I don't shoot cast subs. My carbine gas will not cycle UMC subs but they shoot OK. You may need to enlarge the gas port on the barrel (did that on the 1:7 to 0.097") & run a REAL wet BCG. The nick doesn't go all the way round the nose so it is NOT hitting the groove. Junk from the nick will probably cause you some jams later. Yes, I'm changing back to the Lee lock ring and NOT tightening the FCD down. My lesson learned - pulling 60 rnds. My next test is to get 170 gr. to shoot good sans GC @ 1600 or so. In the mean time, you can single load them to practice your shooting skills - and see how much chambering damage affects your accuracy. Actually I'd work on shooting skills with supers - time in barrel and trigger pull affect accuracy. Get a super boolit and try around 1500 fps.

[Rich22]

OK, cycle a dummy REAL slow and watch the ejection port. Watch for a 3 point bind when chambering. Nose hits edge of chamber. Solution for this is grinding the front edge of the mag lip til the bind goes away (rnd has to pop up to get pushed into the chamber - have to watch it as subs are heavy and nose dive can happen - jams then). You are trying to push a 2' long straight wall boolit into the hole. Chamber some dummys and then check for bent boolits by rolling on a flat surface. I run 1.95" COAL in my supers, short for the mag but just barely miss binding. Barrel maker was sent dummy rnds and he throated it right - ~0.2" - much shorter than most as I don't shoot cast subs. My carbine gas will not cycle UMC subs but they shoot OK. You may need to enlarge the gas port on the barrel (did that on the 1:7 to 0.097") & run a REAL wet BCG. The nick doesn't go all the way round the nose so it is NOT hitting the groove. Junk from the nick will probably cause you some jams later. Yes, I'm changing back to the Lee lock ring and NOT tightening the FCD down. My lesson learned - pulling 60 rnds. My next test is to get 170 gr. to shoot good sans GC @ 1600 or so. In the mean time, you can single load them to practice your shooting skills - and see how much chambering damage affects your accuracy. Actually I'd work on shooting skills with supers - time in barrel and trigger pull affect accuracy. Get a super boolit and try around 1500 fps.

Ok, I will check out the fit through the ejection port tomorrow hopefully. I can grind a few mags without too much issue, if I have to do all of them that I have then that will be an issue. The pmags would not even lock in with the 247s. I tried to get supers to work with a 311155 but the nose is .305 and flat out refuses to chamber in this gun. The 311247 is the only other mold that I have for 30 cal at the moment so I would like to find a load and mag combo that will work with this thing. Thinking I need to crank up the powder, bad part is I do not have much 4227 tons of H110 but only 4 lbs 4227

[Smk SHoe]

Working on 300 BO ammo myself right now. Was loading last night and all was good till i noticed that I had barely buckled a couple shoulders. Was putting on a decent crimp ( not to much) but only thing I can think of is the brass was a couple thou longer than most and the crimp pushed it over the edge. Seated the bullets a little deeper and dialed back the crimp and blasted thru the 50 rds loaded after I found the problem.

[Rich22]

As far as accuracy goes, the 247s shoot very well. It is my skills and not the bullets that are the main issue. Some of the loads I am getting keyholing but I am not getting any reliability out of the gun as far as cycling so once that is fixed then I will look at getting a load that cycles and has excellent accuracy.