If you want to try Ron's trick without having to glue beaucoup weights to clips, I have a possible solution.

I cast bullets for a .45-70 rifle. The bullets weigh 510 grains each, that is a trifle under 1 1/8 ounce. They can be glued to the clip or tied on with string or fishing line, or taped on with duct-tape or elecrical tape. This will allow one bullet per clip, giving a slightly greater weight per clip than using two half ounce fishing weights.

I will be glad to sell unlubed bullets for $00.25 USD each plus shipping.