Tndeer Logo

Page 1 of 2 12>
Topic Options
#3353013 - 09/09/13 03:29 PM Loose Brech Plug or to much powder????
volsgo1
10 Point


Registered: 12/19/02
Posts: 4766
Loc: Collierville, TN. 38017

Offline
Shooting a slufoot HR4570 conversion the first time with FullStream and 280longshot this weekend.

I had Bore sighted the scope prior to coming out to shoot and it was pretty dang close on the first shot at 50 yards made several follow up shots to get it dialed in at 50. Moved out to a hundred yards expecting similiar results.

At 100 I was not even on paper. After a few shots to verify what was going on I assumed Id blown up my ZA-3 Minox scope. We removed the breech plug to check the bores alignment with the cross hairs (poor mans Bore siter).
What we found was the breech plug was extremely loose. Probably my fault for not snugging it down enough. But the bore and the crosshairs of the scope were dead on.

Thinking that the loose breech plug might be the problem but not knowing how that could have affected accuracy We cleaned the plug, snugged it in the barrel with a socket and then shot at 25 yards. 1/2 low of bullseye??? Im back in business so I think. I shoot one last shot at 100 yards and vertically I am good but about 6 inches low. That was my last shot for the day.

Questions:
1. Could the loose breech plug have caused the accuracy issues?
2. Was 62 grains of n120 to much and did that cause the issue at longer distances as it was fairly accurate out to 50. I might add that FullStream was shooting 58 grains of the n120 out of his 45/70 conversion and getting great groups at 200 yards. Can 4 grains make such a huge difference?

I waited for a cool barrell between all shots
62 grains, barnes 195, light blue harvester sabots
Chroned speed 2830
None of the recovered sabots appreared to be blown

Thoughts from the experts???
_________________________
Vegiterian- An old Indian word for Bad Hunter.

Top
#3353059 - 09/09/13 03:56 PM Re: Loose Brech Plug or to much powder???? [Re: volsgo1]
Rubberduck270
10 Point


Registered: 11/01/10
Posts: 2742
Loc: Lawrence Co.

content Online
You'll probly get a different answer from the boys on Doug's but here's my suggestion (based off my stainless H&R conversion).

Scrub the barrel good and make sure you don't have any plastic fouling. A single blown sabot can cause plastic build up instantly AND warm sabots in a warm barrel causes the gradual build up to escalate quickly. Polishing the barrel with JB Bore paste will help from getting plastic build up.

On your next outing take an infrared thermometer with you and verify barrel temp shot to shot. A cooling rod will help your efforts too. A hot barrel acts a lot like a loose scope mount or base. Always in the ballpark but never consistent and very random.

I personally don't think the plug could have caused this much trouble. I don't tighten mine down with a wrench, I just run it in and out with a socket and extension so it's pretty much just finger tight. If the plug was several turns out then the action wouldn't have closed and locked with a primer in it.
_________________________
Smokeless Muzzleloading: It ain't your Grampa's flintlock

Top
#3353109 - 09/09/13 04:35 PM Re: Loose Brech Plug or to much powder???? [Re: Rubberduck270]
fullstream
8 Point


Registered: 12/04/06
Posts: 1490
Loc: tipton

Offline
 Originally Posted By: Rubberduck270
You'll probly get a different answer from the boys on Doug's but here's my suggestion (based off my stainless H&R conversion).

Scrub the barrel good and make sure you don't have any plastic fouling. A single blown sabot can cause plastic build up instantly AND warm sabots in a warm barrel causes the gradual build up to escalate quickly. Polishing the barrel with JB Bore paste will help from getting plastic build up.

On your next outing take an infrared thermometer with you and verify barrel temp shot to shot. A cooling rod will help your efforts too. A hot barrel acts a lot like a loose scope mount or base. Always in the ballpark but never consistent and very random.

I personally don't think the plug could have caused this much trouble. I don't tighten mine down with a wrench, I just run it in and out with a socket and extension so it's pretty much just finger tight. If the plug was several turns out then the action wouldn't have closed and locked with a primer in it.


I believe based on what he was shooting (2830) it was a combination of too hot of a load plus loose breech plug. He is gonna back it down to 58gns for next weekend & cooler temps & I believe we will have alot better rests from hei H&R.

Top
#3353118 - 09/09/13 04:46 PM Re: Loose Brech Plug or to much powder???? [Re: fullstream]
Rubberduck270
10 Point


Registered: 11/01/10
Posts: 2742
Loc: Lawrence Co.

content Online
If his sabots looked good the load shouldn't have been too hot.
_________________________
Smokeless Muzzleloading: It ain't your Grampa's flintlock

Top
#3353166 - 09/09/13 05:33 PM Re: Loose Brech Plug or to much powder???? [Re: Rubberduck270]
CR500AFX
6 Point


Registered: 08/10/12
Posts: 603
Loc: ANDERSON CO.

Offline
The first time a breech plug is installed, it should be tightened with a ratchet to at least 10 foot lbs. This mates the breech plug and counter bored surface of the barrel. I can't remember where I read that but I think it was in some Savage literature. Once this is done, the breech plug will seat more firmly when snugged. Think of it like lapping valves in a cylinder head.
_________________________
She told me if I go riding/hunting one more time she's gonna leave me......I'm gonna miss her...

Top
#3353352 - 09/09/13 08:32 PM Re: Loose Brech Plug or to much powder???? [Re: CR500AFX]
KPH
10 Point


Registered: 08/06/05
Posts: 3626
Loc: Hendersonville Tenn

Offline
Now I am not only going to have to take my infrared now I have to take my torque wrench. Witch those maybe some good ideas.
_________________________
when I die please don't let the wife sale my guns for what I told her I paid for them

Top
#3353371 - 09/09/13 08:44 PM Re: Loose Brech Plug or to much powder???? [Re: KPH]
Rubberduck270
10 Point


Registered: 11/01/10
Posts: 2742
Loc: Lawrence Co.

content Online
Ya'll can do as you wish but I'm not going more than hand tight. Teflon tape will help if it keeps wanting to work loose but I wouldn't start trying to torque it down.
_________________________
Smokeless Muzzleloading: It ain't your Grampa's flintlock

Top
#3353410 - 09/09/13 09:13 PM Re: Loose Brech Plug or to much powder???? [Re: Rubberduck270]
volsgo1
10 Point


Registered: 12/19/02
Posts: 4766
Loc: Collierville, TN. 38017

Offline
Thx guys for the input. A shooting i will go. Cleaned it good tonight. No visible signs of plastic.
_________________________
Vegiterian- An old Indian word for Bad Hunter.

Top
#3353436 - 09/09/13 09:24 PM Re: Loose Brech Plug or to much powder???? [Re: volsgo1]
Rubberduck270
10 Point


Registered: 11/01/10
Posts: 2742
Loc: Lawrence Co.

content Online
Lol you'll have to take my word for it but a lot of the time the plastic is invisible. It takes very little to start causing problems, especially in the heat.

Whats your loading pressure with the barnes? I never could get them to group in mine without knurling.
_________________________
Smokeless Muzzleloading: It ain't your Grampa's flintlock

Top
#3353480 - 09/09/13 09:58 PM Re: Loose Brech Plug or to much powder???? [Re: Rubberduck270]
CR500AFX
6 Point


Registered: 08/10/12
Posts: 603
Loc: ANDERSON CO.

Offline
Lol
_________________________
She told me if I go riding/hunting one more time she's gonna leave me......I'm gonna miss her...

Top
Page 1 of 2 12>


Moderator:  RUGER, Tennessee Todd, Bobby G, Unicam, CBU93, stretch, Kimber45, Mrs.Unicam, Crappie Luck 
Hop to:
Top Posters
4105246
RUGER
86699
Deer Assassin
65056
BSK
60881
Crappie Luck
51376
spitndrum
Newest Members
TboneD, sbhockey, ZachA, DocT, Raegan
13202 Registered Users
Who's Online
110 registered (ruthunter, johnny371, Twinshooter, bowhunterfanatic, HowattHS, ruger7mag, 13 invisible) and 137 anonymous users online.
Forum Stats
13202 Members
42 Forums
91494 Topics
1069622 Posts

Max Online: 788 @ 11/11/13 08:06 PM
Moon Phase
CURRENT MOON
August
Su M Tu W Th F Sa
1 2
3 4 5 6 7 8 9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
31
Forum Donations
The TnDeer.Com Deer Talk Forum is for Tennessee Deer Hunters by Tennessee Deer Hunters. If you enjoy using our Talk Forum and would like to contribute to help in it's up-keep. Just submit your contribution by clicking on the DONATE button below and paying with PayPal or a major credit card. Any amount is much appreciated. Thanks for your support!

TN Burn Safe

Generated in 0.049 seconds in which 0.001 seconds were spent on a total of 15 queries. Zlib compression enabled.