Bullet tumble...

[56-210]

Hey guys,

What i know about reloading is rudimentary...The gun is a sp101 3"

The guy I have doing some reloading for me is a recommended fella, and we have moved into reloading my 327 brass..He knew of the 327 just never reloaded them..So we get the die and some 100gr fmj and do up 300 of them...

He's impressed with what the factory fps is, he reduces the load to what he shows me on the load chart as acceptable just cause he like to be careful...

As the title says we , well me, have Bullet Tumble at 30 feet, lets say 6-7 outta 50 rds...When i brought to his attention he gets back to me, and mentions he has not used the correct recommended primer...(400 and it shoulda been a 200 something like that)

Well got the correct primers on hand and fixing to load up 50 and try it out..I'm trying to avoid some expensive hit and miss experiments as much as possible...So any helpful information anyone has that i can pass on to my guy is appreciated...

Thanks Mark

 

[contender]

I do not think a primer issue would cause bullet tumble.
You didn't provide enough data to point to the reloads as the possible culprit. But, I'll try & offer a few thoughts.
First, bullet tumble can be caused by different things. The rate of twist combined with a bullet not balanced by that rate usually comes to mind. However, a 100 grn FMJ bullet SHOULD mate to a 327 mag just fine. But the shorter SP-101 might not like that bullet. Have you shot other 100 grn bullets in it? if so, were the other bullets lead or jacketed?
Next, velocity can possibily cause it, but if you kept it in the safe range according to the manuels, then I doubt it's the cause. That may be why your friend thinks the primer might be the culprit. It is possible.
Next, have you looked closely (under magnification) the end of the gun barrel? Oftentimes, during cleaning a mis-aligned steel jointed cleaning rod, or something else can very slightly nick the edge of the bore. It'll cause erratic accuracy & even tumbling.
Next, has there been any custom work to the gun? Such as porting of the barrel? If so, look at that as well.

Just throwing out a few thoughts.

 

[56-210]

Thanks Contender,

I have only shot factory purchased ammo so far, American Eagle 100gr jacked soft point, and dont recall any issues when i shot that...

No custom work to the firearm...I have a magnifying glass and see no discernible marks on the bore, that's not to say there isn't, that a more trained eye than mine may see...

Thanks for your reply, i'm meeting up with him this week and will convey your thoughts...

Mark

 

[FergusonTO35]

If you're using .308 bullets for the M1 carbine they are too undersized to work in your revolver. .32 revolver cartridges require bullets .312-.314 in diameter.

 

[djw54]

If you're using .308 bullets for the M1 carbine they are too undersized to work in your revolver. .32 revolver cartridges require bullets .312-.314 in diameter.

That came to mind. Also, run some of these rounds over a chronograph. Let's find out if the velocity is consistently below what the charts say it should be, or if it is consistent at all.

 

[56-210]

Thanks Ferguson,

I actually just got back from running 25 of the factory 100gr JSP through it (nice thing about the southwest, i'm like 3 miles from a shooting spot in the desert) With out a tumble (30ft dirty birds)

IMO I'm fairly certain i dont have a nick in the bore and that it is indeed the bullet...I cant be certain he didnt use a .312/.314 diameter , i was under the impression he did..I'll press him on that..He mentioned the bullets were hard to find, any one wanna give up on their bullet fishing spot?

Thanks Mark

Thx djw54 i know he just got one and we need to chart that too...

 

[mike7mm08]

Midway is showing a good number of different bullets in stock. I also think he might of loaded with 30 carbine bullets. Might of been one of the gunshop "experts" telling him they would work when he could not find the appropriate ones.

http://www.midwayusa.com/find?&sortby=1&itemsperpage=20&newcategorydimensionid=6263

 

[56-210]

Midway is showing a good number of different bullets in stock. I also think he might of loaded with 30 carbine bullets. Might of been one of the gunshop "experts" telling him they would work when he could not find the appropriate ones.

http://www.midwayusa.com/find?&sortby=1&itemsperpage=20&newcategorydimensionid=6263

Whoa! High 5 Mike, thanks for the link..

 

[RR]

Mike, there are "Experts" in Gunshops?

RR

 

[contender]

Good point about the undersized bullets. I'd definately check that. Pull one of the ones from the offending batch to see. If it mikes at .308,,, then you got the wrong bullet.
If so, they are not dangerous, but as you have found, they might not be accurate or may tumble.

 

[56-210]

Lil update for you guys..

He used .312 bullets and were purchased through midway, they were a plinking round and conversely less expensive...We are going to try the Hornady 100gr HP and see if this solves the issue...

Thanks for all the input, suggestions, and help. I'll post back the results once the problem is solved..

Mark

 

[56-210]

Lil update on my OP...Got some Speer 100g HP (312)...Now my reloader bounced the recipe load to full..Had no bullet tumble (shot 40) I guess we concluded the Sp101 327 needs the full power load on the reload...

Thanks for all the replies and offered help.

Shoot safe

Mark