Hot and fouled barrels

[Charlie-NY]

Most of my testing has been with 120gr charges (85gr weighed) of BH209 with 250-300gr sabot bullets in my Encore 209x50. First groups always seem to be better than groups following a dozen shots or so. I run a T17 patch down the bore and then flip it over for another run down the bore in between shots. Admittedly, I'm inpatient and don't let the barrel cool too much. The barrel isn't HOT but it certainly is warm. I do not clean/clear the breech plug until I'm home and doing a thorough cleaning of the entire rifle.

Could the fouled bore or warm barrel be causing the groups to open up?

 

[toytruck]

Try 90 gr. Volume BH 209 and work up if needed. Don't swab between shot's not necessary.

 

[MrTom]

A hot or too warm of barrel can definitely cause groups to open up. If you user name is an indication that you live in New York, you might best be re-thinking how you are not clearing the breech plug. In cold weather. as in hunting scenarios, even small amounts of crud in the flame channel can cause either mis-or dud fires.

And as Toytruck suggests, you may be pushing it too hard at 120 grains. Most people find the best accuracy somewhere between the 90 grains and 110 grains by volume when using the 209 powder.

 

[dbowling]

If your not cleaning flame channel in bp w/drill bit using BH209 depending on number of shots taken that might be your problem also, shooting that hot of a load carbon builds up quicker and effects accuracy.

 

[GM54-120]

T17 is a water based cleaner. Not a good choice when shooting BH209.

 

[BuckDoeHunter]

Try Bestill's combo of half alcohol, half Hoppes, that's what I have and will be trying in the future with my Disc Elite that likes a max charge of BH209.

I know its tough but be patient and wait for the barrel to cool, I set a timer on my phone and don't load until it goes off. You could try a cooling rod to help lower your barrel temps instead of waiting. Try swabbing and then no swabbing to see what works better. I usually don't swab between shots but have been curious to try swabbing between shots to see if it helps.

Some have posted that cleaning the flash channel every few shots helps accuracy, try it and see.

 

[Charlie-NY]

I've got a few things to experiment with this coming week. The gun does shoot very tight groups with the 85/120gr BH209 load but they eventually open up. With the 250gr TMZ sabot @ 2,065 the drops were also surprisingly well matched with the BDC lines (circles) in the Nikon scope. Each holdover represented about 50yds. That's how I was lucky enough to repeatedly slap the gong at 300yds the other day.

Re the T17: In my ML stash that has been sitting around for the last 8 years is a jar of T17 cleaner which does pull a lot of black residue out, and I have a jar of the T17 cleaner & bore seasoner, which I read is for black powder substitutes. I just haven't gotten to that jar yet. Every trip to the range is a learning experience as I get more familiar with my old rifle and some new projectiles.

Thanks for all the feedback.

 

[Charlie-NY]

For those of you who are shooting a 50cal with 120gr of BH209 and sabots; how many times can you reload WITHOUT running a damp patch down the bore? Based on my previous experience I don't recall getting more than 2. ???

For hunting purposes, two is enough but for range shooting I thought swabbing the bore was necessary.

 

[sabotloader]

I would really suggest that you drop any of the T17 products that you might be using, especially, with BH-209 powder. While BH is a BP sub - it really is a slow burning smokeless powder with a bit of Sulphur and Potassium added to qualify as a BP sub.

With BH it is a whole new ball game.

 

[sabotloader]

For those of you who are shooting a 50cal with 120gr of BH209 and sabots; how many times can you reload WITHOUT running a damp patch down the bore? Based on my previous experience I don't recall getting more than 2. ???

For hunting purposes, two is enough but for range shooting I thought swabbing the bore was necessary.

I have gone 10 - 15 shots without running a damp patch... After that many shots I do have to consider drilling out out the flash channel in the BP

Part of your problem may be the build up of T17 residue in the bore.

 

[jsteurrys]

For those of you who are shooting a 50cal with 120gr of BH209 and sabots; how many times can you reload WITHOUT running a damp patch down the bore? Based on my previous experience I don't recall getting more than 2. ???

For hunting purposes, two is enough but for range shooting I thought swabbing the bore was necessary.

The whole range session. I will run a dry patch down the bore when I am done for the day as it makes cleanup with Hoppes much easier and quicker.

 

[MrTom]

For those of you who are shooting a 50cal with 120gr of BH209 and sabots; how many times can you reload WITHOUT running a damp patch down the bore?

To answer this specifically, I shoot all of the guns I take with me to the range between 15 and 20 shots each while using BH209 powder. I'll clear the flash channel of each gun about three times on average, depending on which primers I use. My accuracy does not change between using Winchester blue box primers or CCI standard primers, but what changes is the amount of fouling in the flash channel between the two brands of primers. The barrels see zero patches at the range but are cleaned as soon as I get home.

I find that with sabots the residue from the 209 powder is almost oily feeling and acts somewhat like a barrel lubricant for the next shot. The one hard loading shot in any of my guns will likely be the first when only primer fouling is in the barrels.

In the two .50 cal rifles I shoot targets and hunt with, things go to pot with the accuracy as soon as I push the loads over the 110 grain by volume [77grains weighed] mark with 250 grain to 300 grain bullets, however, my best accuracy with the .50s is with a 250 grain bullet. In the one .45 cal rifle I shoot targets and hunt with, the accuracy starts to fall apart at 100 grains by volume [70 grains by weight] and my accuracy is best using 90 volumetric grains [63 by weight] pushing a 195 grain bullet. As has been mentioned, you are likely pushing the load too hard and by backing up 10 t0 maybe 20 grans of powder you'll see much improved accuracy without losing much bullet energy.

 

[D55]

Heat is an enemy even with sml and sabot-less shooting. I shot about a dozen shots today and results were ok-poor as it got a little warmer later in the morning. Full sun and it didn't allow for decent cooling. I would get 2 cutting the same hole then a flier about 1/2" away. Each flier when I loaded was distinctively easier to push down but the chrono only showed 5-10 fps difference in speed. I was shooting sabot-less and really only out to compare CCI lrmp speed difference against Fed. Match primers. BTW difference was only 10fps faster with the Fed. Match which I am now out of.

 

[LarryBud]

It’s been my impression that a hot barrel will soften the sabot to a point where it won’t grip the bore and projectile as tightly as before. I’m not sure where things cross the line. Probably different with the various sabots.

 

[ENCORE50A]

It’s been my impression that a hot barrel will soften the sabot to a point where it won’t grip the bore and projectile as tightly as before. I’m not sure where things cross the line. Improbable different with the various sabots.

Heat and sabot

 

[rangerod]

It’s been my impression that a hot barrel will soften the sabot to a point where it won’t grip the bore and projectile as tightly as before. I’m not sure where things cross the line. Improbable different with the various sabots.

I couldn't agree more.

 

[mnoland30]

I don't shoot BH 209 because of the cost, but I pull the primer and then swab with a damp patch and then dry patch between shots. That pulls cooler air into the barrel as I swab. If I'm serious about groups, I set my phone timer to 5 minutes, and don't shoot until the timer goes off. Most of my shooting is not in the summer, so things cool down faster.

 

[Charlie-NY]

I shot the ML a bit more today and noticed something interesting. Initial shots were consistent in velocity with a standard deviation in the teens. The last few shots started throwing lead all over the place at 200yds. The velocities varied over 100 ft/sec with carefully weighed charges.

Its either the bore condition or my technique but I "try" to set the bullets down with equal pressure. I continued my practice of using a damp patch between firings. Without it I think I could only get two consecutive sabots down the bore. They seem to get tight fast.

 

[dbowling]

If using bh209 you shouldn't swab between shots guns actually shoot better w/o swabbing. BH209 actually gets slicker loading after you load a couple shots, if you swab makes it load harder. This has been my experience guess yours can vary.
You never did say if you are cleaning flame channel with a drill bit every few shots?
I believe swabbing may cause velocity swings along with inconsistent loading pressure.

 

[GM54-120]

I could shoot many many shots no problem with BH209. So im not sure why yours is getting so tight. Some of my sabot loads are very tight but never seem to get any tighter even after 20+ shots.